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

---

BIGGEST IN TEXAS

More from FoxSports

The Lone Star State hosts the day's biggest matchup as the Astros and Rangers begin a four-game series in Arlington that will help decide the AL West. Houston leads Texas by 1 1/2 games after both teams won Sunday, with the Astros using a five-run ninth to top the Angels 5-3 while the Rangers blew out the A's. Scott Kazmir (7-10, 2.63) goes for Houston while Cole Hamels (9-8, 3.76) pitches on five days' rest for the Rangers.

STICKING AROUND

While the Texas teams battle for the top spot in the AL West, the third-place Angels will try to stay relevant as they open a three-game series at Seattle. Mike Trout homered Sunday and has two in seven games after going a career-long 27 games without a long ball. Garrett Richards (13-10, 3.71) throws for Los Angeles - which is 4 1/2 games behind Houston - against Taijuan Walker (10-8, 4.70).

MORE BOUNTY FOR OLD MEN

David Ortiz and Alex Rodriguez both look to continue historic seasons against AL East rivals. Ortiz slugged his 500th homer on Saturday and now has 34 homers on the season with Boston. Meanwhile, Rodriguez was honored in New York on Sunday for achieving his 3,000th hit earlier in the season and now has 31 homers. They are just the second pair of sluggers 39 or older to hit 30-plus homers in the same season - Barry Bonds (45) and Steve Finley (36) were the first in 2004. The Red Sox open a series at Baltimore while the contending Yankees travel to Tampa Bay.

COORS CRUSH

Nolan Arenado seeks to build on his NL-leading 38 homers and 110 RBIs as the Rockies face the first-place Dodgers in the first of three games. No Rockies player has led the NL in homers since Larry Walker did it in 1997, and Matt Holliday was the last to win the RBI crown, accruing 137 in 2007. Rookie Jon Gray (0-0, 5.17) will pitch against the Dodgers' Clayton Kershaw (13-6, 2.15).

WELL PENNED

The Phillies' Ken Giles is likely due an off day after his pair of scoreless appearances helped Philadelphia salvage a four-game split with the Cubs over the weekend. After picking up the win with 1 1-3 hitless innings Saturday, Giles notched his 13th save in a 7-4 win Sunday. Giles has allowed just two earned runs in his last 26 appearances (0.64 ERA). The Phillies will send rookie Aaron Nola (6-2, 3.56) against the Nationals' Jordan Zimmermann (12-8, 3.32).