Joe Mauer was 20 and in his third professional season when he was promoted to New Britain, the Twins' Class AA farm club. The upgrade in competition at Class AA long has been considered the make-it or break-it point for players in their attempt to ascend to the big leagues.
General Manager Terry Ryan asked Tom Kelly, the former Twins manager, to make a scouting trip to watch Mauer's first few games with the Rock Cats.
"In his first at-bat, Joe was late and fouled the ball almost straight back," Kelly said. "In his second at-bat, he was not quite as late and hit the ball way foul to left. He kept catching up to the increased speed of Double-A, and by the middle of the second game, he was hitting line drives to the middle of the field.
"I called Terry and said, 'I wouldn't worry. Mauer's going to be fine here."
Mauer batted .341 in 2½ months at New Britain and was the Twins starting catcher at age 21 to open the 2004 season.
"That's an unusual case, of course … to get up to speed as quickly as Joe," Kelly said. "We've had other guys who wound up having outstanding careers, like Torii [Hunter], who had to spend two years at the same level, who had to go back to Triple-A after they had been in the majors.
"And some hitters, they put big numbers in the minors with a swing that is a little long, a little loopy, and they are never able to quicken it up."
There is no process in major professional team sports in North America that compares to becoming a competent big-league hitter. There are exceptions — Joe Mauer of the previous decade, Mike Trout of this decade, to name two — with the talent to make rapid adjustments and sweep through a farm system.
For most hitters, the journey starting with rookie ball turns into a magnificent and often painful drama: a requirement to improve five times, to speed up the bat five times, in order to find success in the big leagues.
