MILWAUKEE - Chris Carter made a nice first impression for the Brewers.

Carter hit his first home run for Milwaukee, then had a tiebreaking sacrifice fly in the seventh inning to lead the Brewers over the San Francisco Giants 4-3 Wednesday.

Jeff Samardzija, making his Giants debut after signing a $90 million, five-year contract, allowed three runs and eight hits in 5 1-3 innings, struck out six and walked three. He is 0-5 in 10 starts against Milwaukee.

Samardzija walked the first batter of the game, then a single before Ryan Braun's RBI single. Domingo Santana had a run-scoring single in the second and Carter homered in the third, Samardzija settled down and retired seven of his last nine batters.

"He battled well," Giants manager Bruce Bochy said. "He was off a little bit, but he found a way to keep us in the game. He left the game, it was tied. Great job on his part. Battling with men on base. Pitching well in traffic."

Samardzija's windup was bothering him.

"I thought I was great out of the stretch," he said. "Made some big outs. It was just out of the windup, man, falling behind in the count, putting the leadoff runner on and just asking for a day of fighting out there when that happens."

Carter's third-inning home run was his fourth off Samardzija, the most the big right-hander has allowed. He left Houston to sign with the Brewers after hitting 90 homers during three years with Houston.

"We lost the first game by nine. The game yesterday was a lot closer," Carter said. "So, to come out and win today was good for us going forward, knowing we can beat a team like this."

The Giants won 12-3 on Monday and 2-1 on Tuesday before Carter helped the Brewers avoid the sweep.

With the score 3-all, Javier Lopez (0-1) walked Scooter Gennett leading off the seventh. Braun's single off Cory Gearrin and Buster Posey's passed ball advanced the runners, and Carter's fly to centre helped the Brewers beat the Giants for the second time in their past 12 meetings.

"I was just trying to get it out there far enough to get Scooter in," Carter said. "We don't have to worry about those first couple of games. We're past that now."

Tyler Thornburg (1-0) pitched a one-hit seventh, and Jeremy Jeffress threw a perfect ninth for his first save.

Angel Pagan, who played with two sore knees for most of last season, showed he can still run. The 34-year-old doubled and scored in the first, then tripled off Chris Capuano in the sixth and tied the score 3-all on Posey's sacrifice fly off Blaine Boyer.

Matt Duffy, who hit a two-run homer in Monday's win, led off the second with a solo drive that sailed over a TV camera in deep left-centre.

Milwaukee's Taylor Jungmann allowed two runs — one earned — and three hits in five innings, leaving with a 3-2 lead. He singled and scored in the second.

FIRST SAVE

Jeremy Jeffress converted his second career save and first since April 13, 2011, as a member of the Kansas City Royals against Minnesota.

TIMELY DOUBLE PLAY

With Pagan at third base with one out in the first, Posey grounded to Carter at first. His throw skipped off catcher Jonathan Lucroy's glove as Pagan scored. One batter later, Brandon Belt lofted a fly ball down the left-field line. Third baseman Aaron Hill made a running over-the-shoulder catch, turned and threw a one-hopper to get Posey at the plate for a double play.

UNDER REVIEW

Milwaukee challenged a tag play at second base in the fourth on Belt. After a 1 minute, 56 second review, the call was overturned and Belt was out caught stealing.

TRAINER'S ROOM

Giants: CF Denard Span wasn't feeling well at the start of the game, but pinch hit in the seventh for George Kontos. ... The Giants were one of three teams to begin the season with no players on the disabled list. The other two are in the AL, Chicago and Minnesota.

Brewers: With RHP Corey Knebel (left oblique strain) and LHP Will Smith (right knee sprain) on the 15-day disabled list, LHP Sam Freeman (3-2, 3.23 ERA in 135 appearances) was acquired from Texas for $40,000 after Tuesday night's game. The Rangers had designated him for assignment on March 29. RHP Tyler Cravy was recalled from Triple-A Colorado Springs, and RHP Ariel Pena was designated for assignment.

UP NEXT

Giants: RHP Jake Peavy is to start in San Francisco's home opener Thursday against the Dodgers. Peavy is 14-3 with a 2.38 ERA in 29 starts against Los Angeles.

Brewers: RHP Chase Anderson is slated to make his Milwaukee debut Friday night against Houston. Acquired as part of a five-player deal with the Arizona Diamondbacks, Anderson went 6-6 with a 4.30 ERA in 27 starts last season. He has never faced Houston.