SAN FRANCISCO (AP) -- The Giants are relieved star catcher Buster Posey appears to be OK after getting hit in the helmet with a pitch.
Posey was doing well after being struck by a 94 mph fastball in the first inning Monday, a scary moment in San Francisco's 4-1 victory over the Arizona Diamondbacks during its home opener.
Posey left the game and was to be checked on Monday night and into Tuesday, then re-evaluated. The Giants will take no chances and he is likely to sit out Tuesday's game.
''He's doing good. He's doing fine,'' manager Bruce Bochy said.
Taijuan Walker's 0-1 fastball with two outs in the first inning sent the Gold Glove catcher immediately to ground. Athletic trainer Dave Groeschner sprinted toward the plate and Bochy was right behind. Posey got up on his own but exited the game, with Nick Hundley entering to pinch run and stay in the game behind the plate.
Bochy said if Posey weren't a catcher, he might have been OK to remain in the game, but the Giants wanted to be cautious with the 2012 NL MVP and 2010 NL Rookie of the Year.
''It's a scary moment, dangerous moment,'' Bochy said. ''It's one of the worst sounds you can hear in baseball, the ball hitting the helmet. It's a scary moment. There's been a lot of damage to hitters hit in the head.''
Walker (1-1) was booed at the conclusion of the inning, when he came up to bat and at every other opportunity by the AT&T Park sellout crowd of 42,129. Home run king Barry Bonds was among those in attendance.
''I was a little bit shaken up after hitting Posey in the head,'' Walker said. ''It's always a little scary and I never want to do that.''
Matt Moore (1-1) struck out five in eight impressive innings for the Giants. He worried about his catcher.
''Talking to him after he was like, 'I feel fine,''' Moore said. ''I checked on him a couple times throughout the game and he said it was staying the same. It's definitely nice to know that he's doing well so far.''
The Giants scored three runs in the fourth on a trio of successive plays at the plate. Brandon Crawford doubled, then one out later Joe Panik and Jarrett Parker drew consecutive walks. Walker fielded Moore's chopper midway up the first-base line and fired wildly to home, allowing Crawford and Panik to score. Arizona catcher Jeff Mathis retrieved the ball and also made an errant toss well past the plate. First baseman Paul Goldschmidt got the ball in nearly the same place where Walker had been, and his throw back home was too late as Parker slid across safely. Two errors were charged.
Crawford added a sacrifice fly in the seventh after Hunter Pence doubled to start the inning.
Yasmany Tomas led off the fifth with his first home run of the season for Arizona.
Moore, beginning his first full season with the club after being acquired from Tampa Bay at the 2016 trade deadline, took the loss last Wednesday at Arizona after working 5 1/3 innings.
He got through a 1-2-3 first on seven pitches this time and was on a roll. Moore gave up three hits and didn't walk a batter before new $62 million closer Mark Melancon finished for his second save in as many days and first at home after blowing a chance opening day in Phoenix.
Moore plunked David Peralta on the upper right arm to start the eighth, though it wasn't considered retaliation.
''Everybody realizes that that pitch got away from Taijuan, and I'm hoping that Buster's OK,'' Diamondbacks manager Torey Lovullo said. ''I don't think there was anything retaliatory involved in that, it's just something that got away from Matt Moore. He was a little fatigued, it was deep into his outing and I think it just happened to hit David. It's not a big issue for me.''
The Giants honored longtime MLB senior executive Katy Feeney, who died April 1 at age 68. ''KATY'' was spelled on the out-of-town scoreboard while photos and flowers were in the seat she often occupied during the postseason.
Diamondbacks: Bench coach Ron Gardenhire is away from the club, with Jerry Narron the acting bench coach. Gardenhire was to be in Minnesota to undergo surgery for prostate cancer later this month. ''We'll miss him,'' Lovullo said. ... RHP Jake Barrett (shoulder inflammation) will throw a rehab inning Tuesday at extended spring training, while LHP Jorge De La Rosa will do the same Wednesday.
Giants: Right-handed reliever Hunter Strickland returned from the paternity list and LHP Steven Okert was optioned to Triple-A Sacramento.
Diamondbacks: LHP Robbie Ray, who didn't get a decision against San Francisco last Thursday, is 1-1 with a 3.90 ERA and 37 strikeouts in five career starts vs. the Giants.
Giants: After going 2-0 against Arizona last season, RHP Jeff Samardzija tries to avoid dropping to 0-2 in 2017 vs. the Diamondbacks.
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