Key things to watch for in today's games

Key things to watch for in today's games

The Cardinals and the Pirates have the two best records in the National League, and they'll be eyeing each other warily down the stretch. The two contenders will get a close look at each other this weekend, and All-Star Carlos Martinez will be matched against Pittsburgh's J.A. Happ in tonight's 8:15 p.m. ET series opener.

Martinez has gone 13-6 with a 2.91 ERA during his breakout season, but his latest start was pushed back a few days due to discomfort in his back. Martinez will be working on eight days' rest. The right-hander has been better on the road (7-3, 2.68 ERA) than at home (6-3, 3.14 ERA) this season.

Happ, acquired from the Mariners in a deal at the non-waiver Trade Deadline, has been solid in his first month as a Pirate. Happ has gone 3-1 with a 1.98 ERA in his first five starts with Pittsburgh, and he hasn't faced the Cardinals since 2012. In his career, though, Happ is 1-8 with a 6.79 ERA against St. Louis.

Here are a few other matchups and games to look forward to today.

Going East: TB @ NYY, 7:05 p.m. ET
The Yankees have a strong grip on the AL's top Wild Card slot, and the Rays are hoping to finish strong and get back in the race. Tampa Bay will go into this series one game below .500 and 8 1/2 behind New York in the standings, while the Yankees trail first-place Toronto by 1 1/2 games.

The Yankees will go with rookie Luis Severino in the series opener, and the 21-year-old has been impressive in his brief big league career. Severino is 2-2 with a 2.17 ERA in his first five starts with the Yankees, and he's completed six innings in each of his last four outings.

Jake Odorizzi will start for the Rays, and he's gone 2-2 with a 4.15 ERA in 10 outings since returning from the disabled list. The right-hander was far more effective in the first half, when he pitched to a 5-5 record and a 2.30 ERA. Odorizzi has allowed just 10 home runs in his first 22 starts this season.

Odorizzi goes six-plus innings

Watching Texas: MIN @ HOU, 8:10 p.m. ET
On Friday, when the Twins tangle with the Astros, both teams will have a common interest in watching the scoreboard for the Rangers' game. Houston holds a two-game advantage over Texas in the AL West, and the Twins are chasing the Rangers for the league's second Wild Card slot.

Houston starter Collin McHugh has delivered a 14-7 record and a 3.92 ERA this season, and he'll be pitching for the first time since Aug. 26. McHugh has already set career highs in wins, starts (26) and innings pitched (165 1/3), and Houston wants to keep him fresh for the postseason. The Astros will also have the benefit of George Springer, who was activated on Friday after missing the last two months with a fractured right wrist.

The Twins will go with veteran Mike Pelfrey, and he'll be trying to snap a streak of three straight starts in which he hasn't been able to reach the sixth inning. Pelfrey has notched a 6-8 record and a 3.85 ERA in 25 starts for Minnesota, but he's 2-5 with a 5.59 mark in 13 starts on the road.

McHugh earns 14th win

Head to head: TEX @ LAA, 10:05 p.m. ET
The Rangers have fought their way back to contention on the strength of a 28-16 record since the All-Star break, but they still haven't found a way to solve the Angels. Texas is just 4-8 against Los Angeles this season, but the Angels are 19-26 in the second half as the West race begins to tighten.

Southpaw Martin Perez has made eight starts since returning from a season spent on the sidelines due to Tommy John surgery, and he's shown signs of finding his best form. Perez is 2-1 with a 3.13 ERA in his last five starts, and he's 1-0 with a 1.84 ERA in three career games against the Angels.

The Angels will counter with Garrett Richards, who has gone 12-10 with a 3.80 ERA in 25 starts. Richards made 26 starts for the Angels last year and will tie his career high on Friday. The right-hander has been dominant at home this season, posting an 8-4 record and a 3.09 ERA in 13 starts.

Richards earns win No. 12

Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.