MILWAUKEE (AP) Madison Bumgarner felt under the weather on opening day.
The San Francisco Giants' hitters had something ''contagious'' going, too.
Denard Span homered and drove in five runs in his San Francisco debut, and the Giants beat the Milwaukee Brewers 12-3 on Monday despite a sluggish start from ailing ace Bumgarner.
Span hit a three-run shot with two outs in the eighth inning and Joe Panik and Buster Posey followed with home runs off reliever Ariel Pena.
''That inning we hit the three homers, that says it right there,'' said third baseman Matt Duffy, who helped out with a homer and four RBIs. ''I'd say contagious is a good word right there.''
It marked the first time the Giants had connected for three straight homers on opening day.
It was the first time any team had done it in an opener since the Padres in 1997. The only other time a team to hit three straight homers in an opener was the 1948 Red Sox.
The Giants scored quickly against Wily Peralta and bailed out the ailing Bumgarner, who left after the fifth with a four-run lead. The left-hander allowed five hits, five walks and three runs.
The 2014 World Series MVP looked out of sorts after allowing a homer to deep right in the second to Scooter Gennett, a career .124 hitter against lefties.
Manager Bruce Bochy said an illness was going around the Giants clubhouse, and that Bumgarner had been taking medicine to get ready for his third straight opening day start.
Bumgarner had a fever and the chills on Sunday night, the skipper said.
For Milwaukee, Peralta was tagged five runs and six hits in four innings.
''They just put some good at-bats against him. What they're good at it is putting the ball in play on tough pitches with two strikes,'' manager Craig Counsell said.
The addition of Span paid immediate dividends. The center fielder - who signed a three-year, $31 million deal as a free agent in the offseason - went 2 for 4 and scored twice.
This was the first time that San Francisco had opened a season in Milwaukee. The Giants might remember this trip for reasons other than baseball, too.
On Sunday, the team plane arrived and pulled into the Milwaukee airport next to an aircraft belonging to the campaign of Republican presidential candidate Donald Trump. The Wisconsin presidential primary is Tuesday.
Light snow flurries fell outside Miller Park during the opener, though the stadium's retractable roof kept fans warm and dry.
The Giants still got the start they were looking for in an even-numbered year. They won the World Series in 2010, `12 and `14.
In homering off Bumgarner, Gennett accounted for himself well in trying to prove that he can play full-time against lefties.
''I know I can hit lefties. I know I can hit righties. Just going out there and basically doing what I can and that's putting the bat on the ball and swinging at good pitches,'' Gennett said. ''That's what I can control.''
New starting shortstop Jonathan Villar, acquired from Houston in the offseason, homered off Bumgarner in the third in his Brewers debut.
Giants: Posey is recovering from a flu bug that forced him to sit out a spring training game on Saturday. Bochy said the star catcher was feeling ''washed out'' of late, while the coaching staff was affected last week.
Brewers: P Matt Garza's turn on Wednesday will be skipped after the right-hander left a spring training game on Saturday with shoulder tightness. Counsell said Taylor Jungmann will be moved up to Wednesday, but that Garza could still pitch over the weekend.
Giants: RHP Johnny Cueto makes his Giants debut after signing a $130 million, six-year contract in the offseason. Cueto has won his last six starts against Milwaukee.
Brewers: RHP Jimmy Nelson takes the hill after a solid spring training, going 2-1 with a 1.17 ERA in four starts.
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