The Major League Baseball season began in full swing Monday with two controversial figures receiving vastly different receptions from fans.

President Bush received a loud standing ovation when he took the mound to throw out the ceremonial first pitch in Cincinnati, a Republican-leaning city. He was accompanied by two injured soldiers and a father who lost his son in Afghanistan.

San Francisco Giants slugger Barry Bonds, who is pursuing two legendary home run figures while embroiled in a scandal for alleged use of performance-enhancing drugs, was booed when he came to the plate for the first time in the second inning of the Giants' season-opener against the San Diego Padres in San Diego, also a Republican-leaning city. Bonds promptly hit Jake Peavy's first pitch for a double and scored on a two-out single.

In the ninth inning, a fan threw a syringe in the direction of the Giants left fielder, who finished 1 for 4.

Also in San Diego, Mike Piazza, who has more career home runs than any other catcher, hit a homer in his first at-bat in the second inning against the Giants. The Padres won 6-1.

The first game of the season was played Sunday night when the World Series champion Chicago White Sox routed the Cleveland Indians 10-4 in a game interrupted by nearly a three-hour rain delay. The game ended at 2:10 a.m. EDT.

In other opening-day developments Monday:

• Albert Pujols hit two home runs and teammate Scott Rolen belted a grand slam to lead the St. Louis Cardinals to a 13-5 rout of the Philadelphia Phillies in Philadelphia.
• Jimmy Rollins of the Phillies extended his hitting streak to 37 games with a double in the eighth inning against the Cardinals.
• The Boston Red Sox's Curt Schilling, the hero of the 2004 postseason while pitching injured, threw seven solid innings in helping the Red Sox beat the Texas Rangers 7-3 in Arlington, Texas.
• In New York, Tom Glavine of the New York Mets outpitched Livan Hernandez of the Washington Nationals as the Mets won 3-2.
• In Los Angeles, Adam LaRoche and Andruw Jones hit three-run homers, and the Atlanta Braves spoiled manager Grady Little's debut by beating the Los Angeles Dodgers 11-10 before a disappointed turnout of 56,000 — the largest single-game regular-season crowd in Dodger Stadium history.

Bush became the first sitting president to throw a ceremonial pitch in Cincinnati as the Reds lost 16-7 to the Chicago Cubs. The ball to catcher Jason LaRue was high and off the plate, but Bush called it “my best pitch, which was kind of a slow ball.”

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Little American flags were distributed to the crowd of 42,000 before the game. Fans waved them excitedly as Bush was introduced and drowned out the few scattered protesters, like the family sitting a few rows behind home plate wearing matching red-and-white T-shirts that said “11-04-08” — the date of the next presidential election.