In the world of baseball, there are few players who have made as big an impact as Bryce Harper. The 28-year-old outfielder for the Philadelphia Phillies has been a star since his debut in 2012, winning the National League Rookie of the Year award that same year and earning six All-Star selections and a National League MVP award over the course of his career. But even with all of his accolades, Harper’s latest comeback may be his most impressive yet.

After a disappointing first season with the Phillies in 2019, during which he hit just .260 with 35 home runs and 114 RBI, Harper’s performance suffered even more in 2020. In the shortened season, he hit just .268 with 13 home runs and 33 RBI, leading some fans and analysts to wonder if he was past his prime.

But Harper has come roaring back in 2021, putting up some of the best numbers of his career. As of early May, he was hitting .327 with six home runs and 13 RBI, and had an OPS (on-base plus slugging) of 1.055. He had also already stolen five bases, more than he had in either of the previous two seasons.

Harper’s resurgence has been driven by a number of factors, including a renewed focus on his swing and his physical fitness. In an interview with MLB Network in March, he talked about how he had changed his approach at the plate, saying, “I’m really trying to stay through the baseball and drive the ball to all fields.” He also credited his offseason training regimen with helping him get into the best shape of his life.

But perhaps the biggest factor in Harper’s comeback has been his mental approach to the game. In an interview with The Athletic in April, he talked about how he had taken a step back during the offseason to reflect on his career and his goals. “I think when you sit down and think about your career and where you want to go, it makes you focus more on the little things,” he said. “It makes you focus on what you need to do to get there.”

That focus has translated into a renewed sense of confidence and determination on the field. In a game against the St. Louis Cardinals in April, Harper hit a walk-off double in the ninth inning to give the Phillies a 6-5 victory. After the game, he talked about how much the moment meant to him. “That’s what I live for,” he said. “Those are the moments that you dream of as a kid.”

Harper’s comeback has not only been impressive on a personal level, but it has also had a major impact on his team. The Phillies, who finished in third place in the National League East in both of Harper’s first two seasons with the team, were off to a hot start in 2021, thanks in large part to Harper’s heroics. As of early May, they were in first place in the division, with a record of 15-15.

Of course, it’s still early in the season, and there’s no telling how Harper’s comeback will play out over the long term. But if his performance so far is any indication, it’s clear that he still has plenty of gas left in the tank. And for baseball fans everywhere, that’s a very exciting prospect.