The battle for MLB glory begins on Sunday with the defending champ and its World Series rival looking hard to beat, AFP reports.

The 2013 Major League Baseball season opens on Sunday with a new league for the Houston Astros, San Francisco seeking a third World Series title in four seasons and the New York Yankees hurt but dangerous. The six-month campaign starts with the Astros playing host to the Texas Rangers, Houston moving this year from the National League Central division to the American League West, giving each league three five-team groupings.

That means inter-league games, once unheard of until the best-of-seven World Series title showdown in October, will now be played almost every night of the season after being reserved for only select dates in recent years.

San Francisco's dominating pitchers, including standout Tim Lincecum and left-hander Barry Zito, will be counted upon to keep the Giants in contention while 2012 National League Most Valuable Player Buster Posey and Pablo Sandoval provide batting power.

But the Giants will have to contend with the big-spending Los Angeles Dodgers, whose new owners have poured $230 million into salaries this season, landing pitcher Zack Greinke, southpaw hurlers Ryu Hyun-iin of South Korea and reliever J.P. Howell and relying on Matt Kemp to lead the hitters.

Baseball's biggest spenders, the Yankees, have faced injury and controversy in the offseason.

New doping allegations have surfaced surrounding Alex Rodriguez and a Miami clinic. Curtis Granderson is sidelined until May with a broken arm while Mark Teixeira has a wrist injury that might need season-ending surgery, Derek Jeter is coming off ankle surgery and relief ace Mariano Rivera is back after surgery for one last season before retirement.

Unless C.C. Sabathia can spark the pitchers and Robinson Cano can stabilize sluggers, the Yankees could have a long season in the American League East.

Rising in that division are the Toronto Blue Jays, who landed 2012 NL Cy Young Award winner R.A. Dickey and Mark Buerhle to pitch, doping-disgraced outfielder Melky Cabrera and shortstop Jose Reyes in a bid for their first trip to the playoffs since winning the 1993 World Series.

Detroit third baseman Miguel Cabrera comes off the first Triple Crown season since 1967, leading the AL with a .330 batting average, 44 home runs and 139 runs batted in.

With Torii Hunter, Prince Fielder and Victor Martinez in the lineup around him, he might just do it again and put the Tigers back in the World Series, this time hoping to avoid being swept as they were by the Giants.

Baltimore and Oakland made surprising AL playoff runs last year and return much of their same lineups in a repeat bid, the Orioles taking a wild-card spot and A's edging Texas for the AL West crown.

The Los Angeles Angels welcome ex-Ranger Josh Hamilton to a lineup already boasting Albert Pujols and AL Most Valuable Player runner-up Mike Trout, giving the Rangers headaches while anything better than 107 losses will be a step up for Houston.

NL East defending champion Washington boasts young pitching star Stephen Strasburg and batting hero Bryce Harper and added Rafael Soriano to the bullpen of what could become a powerhouse after decades of baseball futility in the US capital.

Ageing veterans Ryan Howard, Chase Utley and Jimmy Rollins make Philadelphia a threat and Roy Halladay gives the Phillies strength on the mound, but time is running out.

Cincinnati boasts Cuban left-handed closer Aroldis Chapman and St. Louis signed pitcher Adam Wainwright to a long-term deal, helping offset the expected loss of pitcher Chris Carpenter and shortstop Rafael Furcal to injury for the season.