By Jason Beck / MLB.com

In 34 games and 134 at-bats, Carlos Peña has batted .291 with six home runs and 28 RBIs for the Licey Tigers in the Dominican League. (Mark Duncan/AP)

The Tigers' Winter League campaigns were about young players shedding some growing pains after a 119-loss season that furthered many questions. Manager Alan Trammell encouraged as many players as he could to play this winter with an eye on improvement. But the best performances came from players for whom winter ball is a natural.

Peña volunteered to play despite a mid-December wedding; that's how much he wanted to improve after hitting .248 with 18 homers and 50 RBIs in 2003. The native Dominican rejoined his long-time team, the Licey Tigers, with a goal to boost his offense while making pitchers work.

Mission accomplished. After starting out the season with some torrid performances, Peña settled into the numbers fans have looked forward to seeing from him. In 34 games and 134 at-bats, Peña has batted .291 with six home runs and 28 RBIs. Just as important, he struck out 30 times and drew 17 walks, bettering both paces from his last two Major League seasons. He also hit his nuptials head-on in his wedding ceremony. He rejoined the club this month, nailing a go-ahead two-run homer Tuesday in a 5-1 win over Gigantes del Norte in round-robin postseason play.

Rodney nailed down the closer's job for the Tigers in September, having honed his changeup to trip up Major League hitters and complement his upper-90s fastball. He was part of a bullpen by committee for the Dominican League's Escogido Lions, but he made the most of his limited innings. In 17 innings over 10 appearances, Rodney allowed one run and sturck out 22 against five walks. He posted a team-high three saves for a squad that won just 15 games for the season. Two other saves came from fellow Detroit reliever Franklyn German, who allowed three earned runs in 9 2/3 innings.

But none of them had as much of a breakout winter as Infante, the flashy shortstop whose struggles at the plate and concentration lapses cost him the starting job in Detroit last June. He probably won't win back his starting job with the Tigers soon thanks to last week's trade for Carlos Guillen. But his performance in the Venezuelan League likely did plenty of reinforce his status as one of the Tigers' top prospects and make the club think about what to do at season's end, when Guillen can declare free agency.

Months after barely claiming a .200 average between Detroit and Triple-A Toledo, Infante nearly claimed a batting title to bring back to the States this spring. His .343 average in 233 at-bats was good for third, but it showed he could take a hot start and keep it up from an average standpoint.

Moreover, Infante closed the regular season with a splash. He went 5-for-5 in the Oriente Caribes' 20-4 rout against the Tiburones de la Guaira on Dec. 18. A day later, he went 2-for-4 with a double, and the late-season surge was on. He raised his average from .335 to .350 in four days before settling back down to about the mid-way point in between over the final week.

Performances in Puerto Rico were mixed. Brian Schmack became a regular closer for Caguas, saving six games in 19 appearances while posting a 1.50 ERA. Craig Monroe hit over .300 through the first couple weeks of Ponce's schedule before dropping to .225 in 26 games. Andres Torres earned regular action there, too, but hit .220 in 34 contests.

Now, dominating in winter ball isn't the same as Major League success. But for the Tigers, it's a big-league reason for optimism.

Jason Beck is a reporter for MLB.com. This story was not subject to approval by Major League Baseball or its clubs.