MLB Today: Bumgarner vs. Greinke; rosters reboot

A look at what's happening all around the major leagues Tuesday:

ACE IT

Giants vs. Dodgers, Madison Bumgarner vs. Zack Greinke. A marquee matchup as San Francisco tries to draw closer to LA in the NL West. Bumgarner ranks among the big league leaders with a 16-6 record and 192 strikeouts. Greinke goes into this start at Dodger Stadium with a majors-best 1.61 ERA.

ROSTER EXPANSION

Clubs are limited to 25 active players through the end of August, but as of Sept. 1, they're allowed to carry any player on the 40-man roster. The Chicago Cubs are expected to use the extra space to recall Javier Baez, while the New York Mets have already announced they'll promote catcher Kevin Plawecki. Other youngsters who may see the majors in September: Corey Seager (Los Angeles Dodgers), Blake Snell (Tampa Bay Rays), Jose Berrios (Minnesota Twins) and Jurickson Profar (Texas Rangers).

LOCKED IN

Too late now for teams to add players for the postseason. The Chicago Cubs beat the deadline by getting outfielder Austin Jackson from Seattle on Monday and the Kansas City Royals got outfielder/DH Jonny Gomes from Atlanta. Players acquired after Aug. 31 aren't eligible for their new teams in the playoffs.

RESHUFFLED ROTATION

Pittsburgh Pirates ace Gerrit Cole (15-7, 2.44 ERA) starts at Milwaukee. He originally was set to pitch Wednesday, but was moved up a day so he can start Sunday night at NL Central-leading St. Louis.

HEADIN' HOME

The Kansas City Royals return to Kauffman Stadium with the best record in the AL, ready to face Detroit in the opener of a nine-game homestand. Kansas City starter Johnny Cueto is 2-3 since being acquired from the Cincinnati Reds. Detroit Tigers starter Justin Verlander lost his no-hit bid in the ninth inning last week against the Los Angeles Angels.

BACK LATER

Marco Gonzales will be promoted from Triple-A to start for the St. Louis Cardinals in place of Carlos Martinez vs. the Washington Nationals. Martinez hurt his back in his last outing and is expected to miss just one start - manager Mike Matheny says the team had already been trying to get some rest for Martinez.