September baseball began on Monday and the final stretch of the regular season will take place over the next four weeks. As the postseason approaches, a number of teams likely made the final significant roster moves to prepare themselves for crunch time.

The AL Central leading Kansas City Royals activated first baseman Eric Hosmer from the disabled list on Monday after the 24-year-old missed over a month with a fracture in his right hand. He was cleared to swing a bat last week and spent the weekend with Triple-A Omaha where he went 3-for-10 with a home run, three RBIs, two runs scored and a walk. Although Billy Butler filled in effectively for Hosmer, his defense was missed during his prolonged absence.

The Royals also promoted Brandon Finnegan from Double-A Northwest Arkansas after the left-hander amassed a 1.33 ERA, 0.89 WHIP and 26 strikeouts in 27 innings (13 total appearances and five starts) in both Double-A and Class-A Wilmington. He'll likely be used out of the bullpen to gain some major league experience, and if all goes well, he could continue with the team if they make the postseason. Kansas City holds a half-game lead over the Detroit Tigers in the AL Central division.

The Cleveland Indians sit four games behind the Royals and just activated designated hitter Jason Giambi from the 60-day disabled list after he missed action since June 12 because of a broken rib and strained calf. Cleveland has lost Nick Swisher for the remainder of the season, so Giambi will provide a good power bat in his place. Last year with the team, Giambi batted .282 with nine home runs and 31 RBIs in 71 games and helped them earn a wild card playoff spot. Manager Terry Francona says he's excited to have the lefty back for September while the team looks to make a late season run.

In the NL Central, the St. Louis Cardinals took the sole division lead for the first time all season with yesterday's victory over the Pittsburgh Pirates and Milwaukee's loss to the Cubs. But they had to make a change in the rotation because of Justin Masterson's struggles since being acquired from the Cleveland Indians. In six starts with St. Louis, the right-hander is 2-3 with a 7.90 ERA and 1.65 WHIP in just 27 1/3 innings. Manager Mike Matheny announced Masterson's move to the bullpen, and it looks as if Michael Wacha will be joining the rotation after his rehab assignment with Double-A Springfield. But in the meantime, Marco Gonzales or Tyler Lyons will be the fifth starter.

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