PHOENIX -- The Milwaukee Brewers made one offseason change to a starting rotation that ranked ninth in the National League with a 3.69 ERA and 11th in strikeouts with 786 last year. Yovani Gallardo, the team's Opening Day starter for five straight seasons, left for Texas by trade in January. His departure paves the way for prospect Jimmy Nelson, who went 2-9 with a 4.93 ERA in 14 appearances with the big club in 2014.

Just make sure not to say that Nelson is replacing Gallardo.

"Jimmy is not the guy taking over for Yovani," manager Ron Roenicke said. "That's the job for Kyle and Garza -- to take over for what Yo was doing."

Kyle Lohse, 36, and Matt Garza, 31, have the most established track records in a rotation that also includes Wily Peralta and Mike Fiers. Assuming the Brewers know what they have in their two veterans, the performance of the other three starters will help determine if they can hang with the Cardinals and Pirates (and maybe the Cubs and Reds) in the National League Central.

Lohse, one of the more perceptive pitchers you'll find, provided a quick scouting take on Milwaukee's three less experienced starters:

• Peralta, 25, brings a little Bartolo Colon to the table with his 6-foot-1, 245-pound frame. He threw his fastball 66 percent of the time last year and his slider 29 percent, with the changeup basically as a "show" pitch. He won 17 games in 2014 in part because he increased his rate of runners stranded from 66 percent to 76 percent and did a better job of dialing back on his emotions in tight spots.

"I've talked to him a lot about not getting wrapped up in situations on the field," Lohse said. "The year before, he would let innings get away from him. That happened quite often to me earlier in my career and I found a formula for success, I guess, and tried to share that with him. Maybe it helped. He learned how to bear down and not try to do too much, and he made a lot of improvements in that area. With stuff like his, he has a tendency to overthrow at times, and his sinker becomes flat."

• Fiers, 29, landed in the news in an unfortunate way when he hit the Miami Marlins' Giancarlo Stanton in the face with a fastball in September. But he pitched extremely well, averaging 9.5 strikeouts per nine and logging a 2.13 ERA in 71 2/3 innings.

"He has great deception," Lohse said. "He throws that 90 mile an hour fastball and guys don't pick it up because of the mechanics of his delivery. He throws the fastball up in the zone way more than I could ever get away with, and the reason is because he has a good curveball that plays off that. Hitters have changed their swings over time, and he's definitely taken advantage of some of those changes."

• Nelson throws in the mid-90s, but he dealt with some control issues in the minors and some scouts wonder if he might be best suited for the bullpen. His main objectives this year are developing his changeup and doing a better job of throwing strikes down in the zone.

"We saw him get a little wild last year," Lohse said. "If guys can discount one of your pitches knowing you probably can't throw it for a strike, it's tough to get through an outing when they've eliminated you down to one or 1½ pitches and don't have to worry about anything else. He just has to be more consistent in being around the zone with all of his pitches."

One thing Nelson won't have to worry about is replacing Gallardo. The Brewers are taking pains not to heap that load on his shoulders.

Return of the D-Train

Dontrelle Willis is a long shot to make Milwaukee's Opening Day bullpen. He hasn't pitched in the majors since 2011, and the Brewers have two lefty relief locks in Will Smith and Neal Cotts (although as Roenicke is quick to point out, Cotts' numbers are relatively similar versus lefties and righties).

But in the early stages of camp, Willis has made a positive impression and become a favorite among teammates and the Milwaukee media.

"He's always so positive and upbeat," outfielder Ryan Braun said. "He's a fun guy to be around -- he really is."

Willis fell a long way after winning 22 games with the Marlins and finishing second to Chris Carpenter in the National League Cy Young Award race in 2005. Since 2010, he has pitched for the Diamondbacks, Giants (twice), Reds, Phillies, Orioles, Cubs and Angels organizations and made several stops in independent ball.

Dodgers shortstop Jimmy Rollins, who grew up in Alameda, California, with Willis, theorizes that the D-Train's biggest problem through the years was "too many pitching coaches." Rollins thinks that teams spent so much time tinkering with Willis' unorthodox motion, it eventually made him tentative and sapped him of his confidence and natural exuberance for the game.

Willis doesn't necessarily subscribe to that theory. And he certainly won't use it as an excuse for his career travails.

"If that's what it was, that's nobody's fault but my own," Willis said.

Willis lost 19 pounds over the winter and threw the ball well enough in a January workout in Phoenix that multiple teams called to express interest in offering him a minor league deal. Now that he's in the Brewers' camp, he plans to enjoy every minute of the experience -- right down to the drudgery of pitchers' fielding practice.

"When I was in independent ball I thought, 'I'm not going out like this,'" Willis said. "For me to get in camp, it's a prouder moment than winning the World Series [in 2003]. Once you're out, you're out. I'm here today. So God is good, and we're ready to rock."