Royals first baseman Eric Hosmer had a very nice rookie season as a 21-year-old in 2011, but then dropped off significantly last year and continued to struggle early on this season. There were even jokes made when Team USA chose the former No. 3 overall pick to replace Mark Teixeira in the World Baseball Classic this spring.

However, after a rough first couple months Hosmer has turned things around in a big way by hitting .322 with 15 homers, 22 doubles, and a strong 50/32 K/BB ratio in 91 games since June 1. And he’s still just 23 years old, which is younger than many prominent rookies.

Overall he’s hit .302 with an .807 OPS in 141 games as one of just three under-25 first basemen (Freddie Freeman and Anthony Rizzo are the others) across MLB with at least 300 plate appearances.

Beyond this season, here’s a list of all the first basemen since 1990 to qualifying for the batting title at age 23 or younger while posting an adjusted OPS+ above 115: Hosmer, Freeman, Billy Butler, Prince Fielder, Paul Konerko, John Olerud, Jeff Bagwell. That’s it. That’s the whole list.

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