Confidence in Baseball: What We Can (and Can’t) Know

Hall of Famer Rod Carew famously said, “When you’ve learned to believe in yourself, there’s no telling how good a player you can be.” Whether he realized it or not, Carew was synthesizing an important truth about an essential component to elite performance: confidence.

It’s a simple line, but it captures something every athlete—and every fan who’s ever stood in a batter’s box, job interview, or high-pressure moment—instinctively understands: our mindset and beliefs impact how we perform. That belief—what psychologists call confidence—is one of the most important, and often misunderstood, pieces of elite performance.

In my last article I focused on peak experiences and flow states, and today we are going to focus on a related topic: confidence. Will Harris recently wrote an interesting article for Razzball titled Can We Confidently Measure Confidence?, which I want to credit as the source of inspiration for this article. While Will looked at performance data to try to figure out if bat speed variance was correlated with batter hard hit rate, and thus potentially with player confidence, I wanted to approach the same topic from a psychological perspective.

Confidence is a term that we all feel like we “know”, but do we really? What is the relationship between confidence and performance? And what can we “know” about a player’s confidence level?

The Psychology of Confidence: A Sport Psychology Perspective

The history of studying confidence can be traced back to Albert Bandura — a Canadian-American psychologist credited with developing the concept of self-efficacy in the late 1970s. Self-efficacy, which has many similarities to our modern conception of confidence, is a person’s belief in their capacity to execute behaviors necessary to achieve specific outcomes.

To break it down more practically, every person in the world has a level of self-efficacy that they experience. How much self-efficacy we have changes moment-to-moment, like a thermometer rising and falling throughout the day depending on what challenges we face. It’s important to note here that we’re not talking about actual ability, but belief in our ability. "I can do this," or "I got this" would be examples of self-talk for someone with high self-efficacy, whereas "I can’t do this" would be an example of the self-talk of someone with low self-efficacy. Feeling confident also feels good, and so higher levels of self-efficacy are correlated with higher levels of well-being, a topic I covered in an earlier post.

In the context of sport, we’ve also learned that an athlete’s confidence is impacted by a variety of factors such as:

• The outcomes of their performance
• Feedback from relevant people (think coaches, family members, teammates, etc.)
• Comparing themselves with other athletes.

The relationship between confidence and performance

All theoretical approaches hypothesize a positive relationship between confidence and performance. This makes sense because if peak performance is about how effectively you can convert preparation into action, and your expectations and beliefs about yourself can influence performance, then having a strong belief that you have the requisite knowledge, skills, and abilities to succeed in a given situation would improve your ability to convert more of your preparation into action.

Interestingly, it’s been found in meta-analyses that the effect of confidence on performance has a greater impact on high-level athletes than on low-level athletes (Moritz et al., 2000; Woodman et al., 2003), so increasing confidence becomes even more of a focus in professional sports. Confidence can’t magically make you better than you are, but a lack of confidence can make you substantially worse. My belief about hitting a 100 MPH fastball won’t change much—but for an MLB player, confidence can be the difference between unleashing their skills or getting in their own way.

So we can imagine athletes constantly engaging in a mental dance; sizing up the task in front of them and assessing—consciously or unconsciously—their ability to handle the moment. The output of this is their level of confidence, and their level of confidence has an impact on their ability to execute.

In a future post I will write more about the concept of pressure and what it means to be “clutch”, but for now it’s enough to note that the pressure of a moment has a major impact on confidence as well. Pressure magnifies the importance of a moment, making it feel weightier than it otherwise would. While the task of pitching may be the same in the first inning or the ninth, in April or in October, high pressure moments raise the bar of how much ability we believe we need in order to succeed because the risks and consequences of failure feel greater.

Despite there being a positive relationship between confidence and performance, there may also be such a thing as too much confidence. Researchers have suggested that high levels of self-confidence can create a sense of complacency that negatively affects a person’s effort in performing a task (Jekauc et al., 2023).

Another interesting aspect of confidence to consider is that high levels of pre-match confidence have not only been found to positively impact an athlete’s performance, they have also been found to negatively impact their opponent’s confidence. Randy Johnson is one of the most intimidating presences ever to step on a Major League mound. At 6’10”, with a fastball that could touch triple-digits in an era when that was nearly unheard of, Johnson was known for striking fear in the heart of batters from the moment his eyes peered over his glove. It’s no wonder that The Big Unit’s self-confidence must have improved his own performance and hurt the performance of opposing batters!

What can we know about confidence?

Despite what we know about confidence, applying this knowledge as an observer to assess a player’s confidence level is extremely challenging. As we covered earlier, an athlete’s confidence can be influenced by the outcomes of their performance, feedback from relevant people, and the comparisons they make between themselves and other athletes. But athletes are receiving feedback from these experiences constantly, and they often occur outside of the news cycle (feedback from coaches or loved ones for example), or as an inner experience (comparing themselves with others).

It’s made further complicated by the fact that our moment-to-moment confidence is layered on top of trait confidence, or how confident we are generally. This means that no two players will experience the same event in the same way. For example, a batter who has higher trait confidence may be better able to stay within himself during an unlucky stretch of batted balls, whereas one with lower trait confidence might be prone to press earlier, or begin making mechanical adjustments in an attempt to force better outcomes. I’ve long believed that elite closers must have very high trait confidence due to the intense pressure they face each time they come into a game. The mental toughness needed to have a short memory, going right back out, with their team relying on them, a day or two after blowing a save is essential. Walking three batters in a one-run game and then striking out the side? That’s trait confidence at work.

In terms of measuring confidence, there are psychological measures that attempt to capture individual self-efficacy and confidence, but we can’t know where a player would score on those measures without having them complete the questionnaires. Research has found that immediately before a match, the eventual winners had significantly higher levels of self-confidence and lower levels of cortisol than losers, but does this mean that managers should be giving out self-confidence tests and measuring cortisol levels before making their starting lineups? I hope not.

But despite all of the uncertainty, we aren’t completely in the dark. There are some things we can know: We know that confidence impacts performance, and we know its impact is stronger at higher levels of play than lower ones. While we don’t know exactly how each individual player will respond to specific events, we can identify events that could impact a player’s confidence levels and examine performance following those events. In this way, we can look at what happens on and off the diamond through the lens of confidence.

For example, here is a quote from the end of spring training, 2025 from a notable player:

“It obviously sucks because you feel like you've proven everything you've needed to. Sometimes it doesn't feel like it's quite enough. Obviously, you go back there and if you have success, it's: 'Oh, he's supposed to have success because he's already proven it,' and if he doesn't have success, it's, 'Oh, well, obviously he's fallen off.' It's kind of a lose-lose going to Norfolk.”

This was Orioles first-baseman Coby Mayo after learning that he was being sent down to triple-A on March 18th, 2025. Can we make a guess about how this move may have impacted his confidence? In 2024, Mayo was nearly 40% better than league average at Triple-A. But over 45 games in 2025, he’s performed right around league average. Of course there could be other factors that also contribute to an explanation of this drop in performance for the 23-year-old, but my point is that if we examine decisions like this through the lens of confidence, the drop in performance becomes less surprising.

Conclusion

Confidence is both elusive and essential. We know it matters—meta-analyses tell us that it has a measurable impact on performance, particularly at the highest levels of sport. We know it is shaped by a constantly shifting mix of performance outcomes, feedback, comparisons, and trait-level disposition. And we know that while too little confidence can undermine an athlete, too much confidence can be problematic in its own right.

What we don’t know—at least with certainty—is how much an individual player’s confidence in a given moment is impacting their performance. This ingredient, despite our best efforts, is largely hidden from view. But what we can do is widen our lens when we interpret performance. Instead of reducing a slump or surge to mechanics or luck alone, we can ask: how might confidence be part of the story?

Baseball isn’t just a test of physical skill; it’s also a test of belief, resilience, and the ability to step into each at-bat with conviction, knowing that “failure” — on a good day — will occur nearly 3/4 of the time. Helping players learn to cultivate and harness confidence in themselves is as important a part of player development as swing changes or pitching mechanics. If we pay attention, confidence may not just help us understand the players better, it might also help us appreciate the game in a richer, more human way.

Citations

Much of the research cited in this article was drawn on from the following meta-analysis: Jekauc, Darko & Fiedler, Janis & Wunsch, Kathrin & Mülberger, Lea & Burkart, Diana & Kilgus, Alina & Fritsch, Julian. (2023). The effect of self-confidence on performance in sports: a meta-analysis and narrative review. International Review of Sport and Exercise Psychology. 18. 1-27. 10.1080/1750984X.2023.2222376.

Bandura, A. (1977). Self-efficacy: Toward a unifying theory of behavioral change. Psychological Review, 84(2), 191–215. https://doi.org/10.1037/0033-295X.84.2.191