Kevin McGonigle did not need another home run to validate his rookie season. He hit one anyway.

McGonigle launched his 18th home run of the season Sunday afternoon against the Pittsburgh Pirates, putting the finishing touch on a rookie campaign that has moved beyond impressive and into historically significant territory. The 21-year-old, for Baseball-Reference age-season purposes, finished the year hitting .278 with 18 home runs, 97 runs and 95 walks. He became only the fourth rookie since 1947 to record at least 95 runs and 95 walks, joining Jim Gilliam, Joe Morgan and Aaron Judge.

And then there is the number that really puts McGonigle’s season into perspective.

6.9 bWAR.

Among position players in MLB history who produced a rookie season at age 21 or younger, only Mike Trout has been better.

McGonigle Joins Mike Trout in Rare Territory

According to the historical Baseball-Reference leaderboard, Trout produced a staggering 10.5 bWAR during his 2012 rookie season at age 20. McGonigle’s 6.9 bWAR places him second among rookie position players age 21 or younger, ahead of two names that require absolutely no introduction: Ted Williams and Albert Pujols.

The leaderboard looks like this:

That is not a Tigers rookie leaderboard. It is not a list limited to the last 25 years.

That is baseball history.

And McGonigle is sitting between Trout and Williams.

Baseball-Reference’s current data also puts McGonigle at 6.9 WAR over 155 games entering Sunday’s finale, with his value coming from a combination of offense, baserunning and defense rather than one overwhelming statistical category.

McGonigle Did Just About Everything

McGonigle’s season becomes even more impressive when you look beyond WAR.

He reached base 266 times in his first 155 games, and earlier this week he broke Harvey Kuenn’s 73-year-old Tigers rookie record for times reaching base. His combination of runs, doubles, home runs, RBIs and walks also put him in statistical territory no rookie had reached since Ted Williams in 1939.

That came after McGonigle had already joined Williams on another remarkably short rookie list earlier this month.

Then came Sunday.

McGonigle had Detroit’s only hit through the first six innings before leading off the seventh with an opposite-field home run, his 18th of the season. A.J. Hinch eventually removed him in the eighth inning, giving the Comerica Park crowd an opportunity to recognize what it had just watched all season.

It was an appropriate ending.

One of the Greatest Tigers Rookie Seasons Ever

The American League Rookie of the Year voting will come later, and A.J. Hinch has already made his prediction clear. Earlier this week, Hinch also planted his flag for McGonigle’s Rookie of the Year case.

But McGonigle’s rookie season no longer needs an award to tell us how good it was.

A 6.9-WAR rookie season is extraordinary at any age. Doing it during an age-21 season puts McGonigle in a historical category occupied by some of the greatest players baseball has ever seen.

Trout was better.

That’s it.

For a position player this young, nobody else has produced more value during his rookie season than Kevin McGonigle.

Not Williams. Not Pujols.

And McGonigle finished his first trip through Major League Baseball with 18 home runs, elite plate discipline, premium defensive value and one of the greatest rookie seasons the sport has seen.

That’s one heck of a starting point.