"This year's different for me," he continued. "I actually like the way I'm throwing it. I feel comfortable throwing it. I feel like I can throw it for strikes, compared to other years, trying to find a grip and get it."
For at least four Spring Trainings, Bonderman has worked on a changeup to round out his repertoire. None of the previous times has he found a grip that he's comfortable throwing while getting the results he wanted.
After throwing about a half-dozen changeups on Monday against the Rays, he was largely happy with how it felt.
The major difference this year with his changeup, besides the effectiveness, is that he doesn't have to experiment with it as much. He worked with his grip on it while playing catch during the offseason, and he has tweaked it a little this spring with help from teammates.
"It's an easier pitch the way I'm gripping it," he said.
The mechanical part is developing. The next step is confidence.
He gave up a hit with it, a Jason Bartlett double in the second inning, but he also had guys like Jonny Gomes in front on it.
His goal is to be able to throw 12-15 changeups every game to complement his power arsenal. That would be major progress. According to the most recent Bill James Handbook, no starter in the American League with at least 162 innings last year threw a higher percentage of sliders than Bonderman, who was at 34.5 percent. The next highest was teammate Nate Robertson at 22.6 percent.
"I'm going to throw it," Bonderman said of the changeup. "It's just a matter of hopefully by the end of this year, that I can throw it in any count.
"I'm just looking by the time the season's over that I have enough confidence to throw it like [Justin] Verlander and Kenny [Rogers]. Anytime I feel like I can pull the string on somebody, it can help me. It puts something else in the guy's mind that I can throw that pitch for a strike. If I can do it, it's going to help me out tremendously."
Manager Jim Leyland's view on Bonderman and his changeup hasn't changed in two years.
"If he masters his changeup," Leyland said, "he's going to go from a good Major League pitcher to a big-time winner, in my opinion."
After watching the pitch on Monday, Leyland was encouraged.
"If he can bottle that, he'll be home free," Leyland said.
Mantei hurting: What had been an encouraging comeback campaign for reliever Matt Mantei has hit an obstacle. Mantei left the complex Monday morning after feeling discomfort in his shoulder following a rough outing Sunday against the Indians.
Mantei gave up two runs on two hits and a walk in an inning of work in that performance, struggling with command throughout. Afterwards, he pinned the struggles to a problem with his mechanics.
"He didn't feel right in his shoulder yesterday," Leyland said. "I don't know what his plans are."
Booth Newspapers and the Detroit Free Press cited Mantei's agent, Bob Garber, as saying that Mantei will have a doctor examine his shoulder.
Any major injury would likely lead to his retirement. When Spring Training began last month, Mantei characterized this as his last attempt at pitching. If he was injured again, he expected to retire.
Inge won't catch: Brandon Inge's utility work will continue with a start in center field Wednesday at home against the Phillies, but don't expect to see much more of him behind the plate.
"It's obvious he does not want to catch," Leyland said. "I'm not going to force someone to catch that doesn't want to catch. He's made it plain and simple to everybody."
After Inge made his first start at catcher on Sunday, he said that the demands of catching were carried with him when he stepped up to hit.
That saga is further complicated by Vance Wilson, whose timetable for a return behind the plate remains unclear. At this point, it appears questionable whether he'll be ready for Opening Day.
If he isn't ready, non-roster catcher Dane Sardinha would appear the most likely option to back up Ivan Rodriguez when the regular season begins. However, that's not certain, and Leyland said they could have to improvise.
"We'll have a second catcher," Leyland said. "I have no clue who it's going to be. Could it be Brandon Inge? That could be possible. Could it be Sardinha? That's possible. Could it be Vance Wilson? That's possible."
Up next: Robertson will make his second start of the spring on Tuesday when the Tigers visit the Astros for a 1:05 p.m. ET game at Osceola County Stadium in Kissimmee. Macay McBride, Francis Beltran, Todd Jones, Tim Byrdak and Preston Larrison are scheduled to pitch in relief. Among the position players expected to make the trip are Magglio Ordonez, Rodriguez, Carlos Guillen, Placido Polanco and Edgar Renteria.