MINNEAPOLIS -- Matt Garza's newfound effectiveness on the mound has been linked with his ability to now mix in all of his pitches. But Garza credits one pitch as being a bigger difference maker than any of the rest -- his changeup. It's a pitch that Garza worked on throughout Spring Training, but didn't really master until he was down at Triple-A Rochester to start the year. Garza still says he doesn't feel the pitch is quite perfect yet, but it's given him another option to go to during his starts.
"It's still a work in progress," Garza said of the pitch. "But it took me a month, month and a half to get the grip going on the changeup. The difference is that I was forcing it and one day it just came to me and clicked. Ever since then, I've been confident in it." Garza said that one of the keys to the development of his changeup was working with left-hander Dave Gassner in Rochester. "Probably the best way to teach pitchers pitches is to work with someone that has a good one, and Gassner's key pitch is a changeup," Twins pitching coach Rick Anderson said. "So I told [Garza] that was the perfect situation." Though Garza was passed up by a few other pitchers at the start of the year, the extended time in Rochester gave him the time to work on the pitch. Garza said he threw 10-15 changeups a day with Gassner just to get the feel of the pitch. And while the talented prospect wasn't too happy about getting bypassed by other pitchers, he now says that the time to work on the pitch was very beneficial. "I was sent down to Rochester to establish my fastball and be able to change speeds when I needed to," Garza said. "That's what I did, I went down and worked hard on that. And it's proven a good choice on their part." The difference in Garza's confidence with the pitch was noticeable on Tuesday night. Anderson said that Garza shook off a fastball in favor of a changeup, something the pitcher said he had never done previously. Garza threw 97 pitches on Tuesday night, with 34 of those being offspeed pitches. That's a significant difference compared to starts last season when Garza threw just three or four breaking pitches in an outing. But it wasn't just Garza's breaking pitches that were effective. Despite Garza saying that his fastball velocity wasn't there, he was still able to consistently locate the pitch and put hitters away with it. Still, Anderson credited Garza's changeup as being a reason why his fastball was so effective. "Last night there were times when good hitters -- Pudge [Rodriguez] and [Magglio] Ordonez -- were real late on it but they had seen some changeups in there too," Anderson said of the fastball. "Adding that changeup opens it up for him to be able to make more mistakes. It's neat that he trusts it now and it shows in the way he pitched." Back to Minnesota: Glen Perkins has been taken off his rehab assignment, and he is on his way back to Minnesota to have his left shoulder re-examined by the Twins' doctors. Twins general manager Terry Ryan said that Perkins is scheduled to be examined by Dr. Dan Buss on Friday to determine the severity of the pitcher's recent setback. Perkins was shut down after pitching just one inning in his first rehab start for Class A Fort Myers on Saturday. The left-hander was taken out of the game after feeling the same pain in the back of his shoulder that caused him to leave a game against the Rangers on May 21. "Obviously, there's a little more there and we want to see where we're at," Twins manager Ron Gardenhire said. "It doesn't look good, but we'll let them decide that and go from there." Starting over: The Twins have extended the rehab assignment of outfielder Rondell White for another 20 days. Due to the extension, White must sit out five days but he's expected to play again on Saturday. White had been sidelined recently due to a sore hamstring, but he's feeling better and has started working out. The plan is for White to play a few games in Florida and then possibly be moved to another Minor League club. The concern is that maybe the heat and humidity are aggravating problems for White. And the thought is a change in location might be the key to getting him back healthy. "The extreme heat might be affecting him," Gardenhire said. "We'll see how it goes. We're trying different things." Limited concern: Shortstop Jason Bartlett recorded his 16th error of the season on Tuesday night, which eventually led to the Tigers only run of the game. But while it was the latest in what has been a slew of errors for Bartlett this season, his skipper doesn't seem all too concerned about the high number. "He's got a few more errors than you'd expect out of him, but he's been playing good baseball," Gardenhire said. The concern for the Twins early this year was that soreness in Bartlett's neck and back might be hindering his play. Those issues haven't exactly disappeared, but Bartlett received a cortisone shot over the All-Star break and reported to his skipper that he's been feeling better. Gardenhire said he's noticed a difference in how his shortstop has played recently. And as for Tuesday's error, he didn't feel it had anything to do with Bartlett's neck issues. "It obviously affected him early, when he was making a lot of bad throws and had a lot of errors come off those throws," Gardenhire said. "But he's using his feet more driving toward the bag and last night he just booted the ball. It happens in the game." Twins tidbits: Torii Hunter celebrated his 32nd birthday on Wednesday. Over the course of his career on his birthday, Hunter has hit .318 (7-for-22) with two home runs and four RBIs. ... The 1-0 loss on Tuesday was the Twins' 26th one-run game of the season. The club is 14-12 in those contests after going 20-11 in one-run games last season. ... Pat Neshek's .130 batting average against is the second lowest among relievers in the Majors, trailing only the Mariners' J.J. Putz (.126). Down on the farm: Kevin Slowey pitched a shutout in Triple-A Rochester's 1-0 victory at Syracuse. The right-hander allowed just three hits, walking one and striking out eight to pick up the win. ... Shortstop Trevor Plouffe was 3-for-4 with an RBI and three runs scored in Double-A New Britain's 11-3 win over Connecticut. ... Right-hander Oswaldo Sosa gave up two runs over 6 2/3 innings in Class A Fort Myers' 6-4 win at Vero Beach. ... Chris Parmelee drew the game-winning walk in the bottom of the ninth to give Class A Beloit a 4-3 victory over Wisconsin. Coming up: The Twins will close out their series with the Tigers on Thursday afternoon in a 12:10 p.m. CT start. Right-hander Scott Baker (4-3, 5.43) will try to improve his career record against the Tigers to over the .500 mark as he faces off against Detroit right-hander Jeremy Bonderman.
Kelly Thesier is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.