If you’ve been a baseball fan long enough, chances are you’ve heard the Abbott and Costello routine, “Who’s on First?”

If you’ve been following Tigers prospects for a while, you still might not have an easy time tracking which position players are playing which positions over the past couple of weeks.

The organization has emphasized positional versatility for its top-hitting prospects ever since Scott Harris took over as president of baseball operations last fall, if not before. With Detroit in need of offense to boost a lineup that has struggled to produce runs in recent years, the last predicament the Tigers want to face is to have a promising young hitter blocked out of Detroit because he plays the same position as an established player.

Over the past couple of weeks, however, the push for versatility among top prospects has picked up momentum. Several ranked prospects have either tried out new positions or revisited old ones -- some as secondary positions, others for potential changes to primary spots. In just about every case, though, the moves are intended to increase their Major League viability.

Here are a handful of notable cases:

• No. 2 prospect Colt Keith has alternated between second and third base this week for Double-A Erie after playing third base all season. He played some second base the last couple years as well as a couple games in the Arizona Fall League. However, it was the first time he’d played second in the Tigers' system since May 11 of last year at High-A West Michigan.

• No. 7 prospect Justyn-Henry Malloy has played three games this week in left field for Triple-A Toledo. Though Malloy split last season between third and left in the Braves' system, he hadn’t played the outfield since joining the Tigers in the Joe Jiménez trade last December. The move predated Riley Greene’s injury in Detroit.

• No. 8 prospect Wenceel Pérez moved last week in Erie from second base to center field, the first outfield work of his career. Pérez has struggled with throwing errors at second since late last year, including nine errors in 25 games there this season. He began his pro career at shortstop before moving to second and third base two years ago at High-A West Michigan.

• No. 16 prospect Manuel Sequera, who moved from shortstop to left field at Class A Lakeland at the start of the season, has moved back to middle infield over the past couple of weeks.

• No. 28 prospect Gage Workman, primarily a shortstop in his pro career, moved to right field last weekend at Erie for the first time. While Workman has been regarded as a fairly solid shortstop, especially for his 6-foot-4, 200-pound frame, some evaluators see his best chance in the Majors as a switch-hitting superutility player.

Of all these moves, Keith and Malloy should be the most interesting situations to follow. The Tigers have a long-term void at third base and either could prove to be the long-term answer there. But the Tigers’ offense could use both bats, regardless of position. Keith’s hitting work at Erie, including a six-hit, two-homer cycle on May 16, has raised anticipation for a promotion to Toledo.

Other notable performances in the Tigers system this week:

Triple-A Toledo
No. 10 prospect Parker Meadows is showing signs of getting out of a rough stretch. He’s batting 9-for-27 with a triple, home run, five RBIs and four runs scored over his last seven games through Saturday.

Double-A Erie
While Keith keeps hitting, keep an eye on right-hander Sawyer Gipson-Long, whose six scoreless innings and eight strikeouts Saturday lowered his ERA to 3.25. The Tigers skipped Gipson-Long’s last start so he could work on adding a cutter to his repertoire, which includes a fastball, slider and changeup. Gipson-Long joined Erie in August as the return prospect from Minnesota in the Michael Fulmer trade.

High-A West Michigan
Top prospect Jace Jung is on a tear, going 10-for-14 with three doubles, two homers and eight RBIs over a four-game stretch through Saturday. He has a sacrifice fly, three walks and two hit-by-pitches in that stretch as well, while striking out only once.

Class A Lakeland
Outfielder Dom Johnson, a 13th-round MLB Draft pick last year out of Kansas State, is batting 10-for-22 over his last seven games through Saturday with two doubles, two homers and 12 RBIs.