Previewing Tuesday's key games

Here, then, is a preview of tonight's four games that will impact the races for the final two berths in the postseason.

Time: 7:05 p.m. ET

Starters: Erik Bedard (5-9, 3.50 ERA) vs. Zach Britton (11-10, 4.44 ERA)

Standings: Red Sox tied with Rays for wild card

• Veteran lefty Erik Bedard missed most of July with a sprained left knee and missed two starts earlier this month when the knee acted up on him again. In his only start since returning, on Sept. 20, he failed to get out of the third inning against the Orioles, throwing 53 pitches in that inning before getting the hook. The combination of the bum knee and that heavy single-inning workload prompted the Red Sox to give him some extra rest, so he makes this start on six-day's rest having thrown just 2 2/3 innings over the last 23 days. Between being acquired from the Mariners at the trading deadline and being sidelined by the knee, he had posted a 3.66 ERA in six starts for Boston.

• Rookie lefty Zach Britton allowed just three runs in 18 innings in his first three starts after returning to the Orioles rotation in late August following trip to the disabled list for a strained pitching shoulder, but has since allowed 14 runs in 22 innings over four starts (5.73 ERA).

• Jarrod Saltalamacchia and Jason Varitek have started each of Boston's first 160 games this season, but neither is likely to be available Tuesday night. Saltalamacchia took a foul-tip off the right collar bone in Monday's game, and while X-rays were negative, he had a huge lump where he was hit and could find throwing difficult. Varitek, meanwhile, was hit by a pitch on his right knee in the opening game of Sunday's double-header and was scratched from Monday's lineup as a result. If neither veteran is able to play, the Red Sox have two rookie catchers on their bench: Ryan Lavarnway and Luis Exposito, who was just called up on Monday.

The Red Sox are also likely to be without Kevin Youkilis (sports hernia) who hasn't played since September 15, Conor Jackson, whose right knee, which he initially injured by running in to a wall in early September, swelled up after a diving catch on Sunday, and Dan Wheeler (forearm) who hasn't pitched since September 7. Saltalamacchia is just 3-for-his-last-33, but righty-swinging Jackson had reached base five times in six previous plate appearances against Britton, the most exposure any Boston hitter has had to the Baltimore rookie.

• The Red Sox haven't won a game that wasn't the nightcap of a double-header since eking out a 4-3 win over the Rays on September 16.

Time: 7:10 p.m. ET

Starters: Bartolo Colon (8-10, 4.02 ERA) vs. Jeremy Hellickson (13-10, 2.90 ERA)

Standings: Rays tied with Red Sox for wild card

• Likely AL Rookie of the Year Hellickson has a 2.03 ERA over his last seven starts, including just two runs allowed in seven innings against the Yankees in his last start. His only career start against the Yankees at home came back in July and produced the same result: two runs allowed in seven innings. Hellickson's ERA is a run lower and he strikes out an extra man per nine innings at Tropicana Field compared to his road rates.

• Bartolo Colon is 0-4 with a 6.18 ERA over his last seven starts and was smacked around by the Rays for seven runs (five earned) in just three innings in his last turn.

• Yankees manager Joe Girardi intends to use all of his top relievers in this game (specifically Rafael Soriano, David Robertson and Mariano Rivera, though possibly lefty Boone Logan and righty Cory Wade as well), to give them a warm-up appearance followed by two days off leading into the Division Series, which starts on Friday. That means that the Yankees may only need four innings out of Colon, so the Rays need to get to him early.

• Ben Zobrist and B.J. Upton are a combined 9-for-14 with two triples, three homers, and four walks against Colon this season. Meanwhile, Robinson Cano, who drove in both Yankees runs on Monday night, one with a solo homer, is 5-for-9 with two doubles, two homers, and two walks against Hellickson in his career.

Time: 7:10 p.m. ET

Starters: Roy Oswalt (8-10, 3.86 ERA) vs. Derek Lowe (9-16, 4.92 ERA)

Standings: Braves lead Cardinals by one game for wild card

• Roy Oswalt has two quality starts in as many appearances against the Braves this season, but has allowed five or more runs in two of his last three starts, doing so against the lowly Astros and Nationals.

• Derek Lowe has been similarly inconsistent, going 0-4 with an 8.24 ERA in September including allowing seven runs (five earned) in five innings in Philadelphia in his first start of the month.

• The Phillies' lineup seems to be divided between hitters who own Lowe (Chase Utley, Hunter Pence, Placido Polanco) and those who are owned by him (Ryan Howard, Jimmy Rollins, Raul Ibañez, Shane Victorino). Only Carlos Ruiz falls in between, hitting a rather empty .320 in 26 career plate appearances against the veteran groundballer.

• The Braves with the best career numbers against Oswalt are shortstops Jack Wilson and Alex Gonzalez. Oswalt has owned Chipper Jones over his career and held Dan Uggla to three hits in 24 at-bats. No other Brave has more than 14 plate appearances against him.

• Speaking of Jones, he doubled and homered on Monday, but also tweaked his sore right knee rounding third base in the sixth inning. Jones stayed in the game and has vowed to play through the pain again tonight, but his range in the field was clearly diminished in the late innings on Monday. Given Jones' poor career performance against Oswalt (.258/.303/.290 in 33 plate appearances), Fredi Gonzalez may be well advised to hold Jones in reserve for a key pinch-hit at-bat later in the game.

Time: 8:05 p.m. ET

Starters: Jake Westbrook (12-9, 4.48 ERA) vs. Henry Sosa (3-5, 4.58 ERA)

Standings: Cardinals trail Braves by one game for wild card

• Jake Westbrook is the only Cardinals starter to be charged with a loss since Chris Carpenter's disaster outing against the Pirates on August 27, taking two losses despite posting a 2.81 in five starts over that span and not allowing more than two earned runs in any of those five outings. He last faced the Astros in late July, holding them to one run over six innings.

• Acquired from the Giants for Jeff Keppinger in July, Sosa made his major league debut in early August and has turned in a quality start in five of his last six turns, posting a 3.82 ERA over that span. This will be his first career appearances against the Cardinals and the first time any of St. Louis's hitters will have faced him.

• The only Astro to have more than a dozen plate appearances against Westbrook is Carlos Lee, who has owned him since their days in the AL Central, putting up a .436/.488/.692 career line in 43 plate appearances against the former Indians groundballer.

• Matt Holliday is 4-for-11 in three games since returning to the lineup on Saturday and had his first multi-hit game and first extra-base hit (a double) in those three games on Monday night. As a result, the heart of the St. Louis order seems to be at full strength for the first time since Holliday injured his right middle finger on September 13. Albert Pujols, Holliday, and Lance Berkman combined to go 5-for-13 with three doubles on Monday night.