Joe Mauer had never played a field position aside from catcher in the major leagues until Thursday's game against the White Sox, when he grabbed a first baseman's mitt and entered a brave new world. Those who have long-clamored for Mauer to switch positions likely applauded -- though this is not permanent, which is what anyone worried about the relative value of Mauer's contract should remember.

That said, it's a good occasion to look at some of the best-hitting catchers in MLB history to see how much they really caught during their careers. The numbers below include all games in which players appeared, excluding pinch- hitting duties but including DH duties, and were culled from www.baseball-reference.com:

• Johnny Bench: 1,693 career games at catcher and 419 games at other positions (190 at third base, 120 at first base, 55 in right field, 52 in left field and two in center field). Total percentage of games at catcher: 80.2.

• Yogi Berra: 1,379 games at catcher and 187 games at other positions (132 in left field, 53 in right field, one at first base and one at third base). Total percentage at catcher: 88.1.

• Carlton Fisk: 2,157 games at catcher and 228 games at other positions (165 at DH, 40 in left field, 21 at first base and two at third base). Total percentage at catcher: 90.4.

• Gary Carter: 2,019 games at catcher and 198 at other positions (123 in right field, 68 at first base, five in left field and two at third base). Total percentage of games at catcher: 91.1.

• Ivan Rodriguez: 2,375 games at catcher and 65 at other positions (57 at DH, 7 at first base and 1 at second base). Total percentage at catcher: 97.3.

• Mauer: 721 at catcher and 110 at other positions (109 at DH, 1 at first base). Total percentage at catcher: 86.8.

• Overall thoughts: Mauer has the second-lowest percentage of career games at catcher (higher than only Bench) of the players looked at, but Mauer has also played virtually all of his games (excluding interleague games in NL parks) with the ability to DH. If not, his catching percentage might be higher. If we accept 85-90 percent of overall games spent at catcher as a benchmark for Mauer to hit going forward, and we guessed he could play 150 games in a season, that would maybe put him at catcher for 130 games and some combination of DH and first base for the other 20. Frankly, that sounds pretty reasonable.

MICHAEL RAND