SAN FRANCISCO -- Giants first baseman Brandon Belt exited Friday's game with concussion symptoms after he was hit in the head by a 79 mph curveball in the sixth inning. After the Giants' 2-1 loss to the D-backs, manager Bruce Bochy said Belt would be re-evaluated Saturday.
On a 2-1 count, D-backs starter Anthony Banda missed with an offering, hitting the first baseman on the back of the helmet. He immediately dropped to the ground, holding the back of his head with his right hand.
He spent a few minutes near the batter's box before head athletic trainer Dave Groeschner and Bochy helped him off the field.
"I'm sure this is probably scaring him a little bit, because he's been through this," Bochy said. "It's not a lot of fun to go through one. Now he's going through another one. ... It's obvious there's some concerns there."

Belt wasn't in the Giants' clubhouse after the game but teammate Buster Posey -- who also has experienced a concussion -- said he sent a text message to the 29-year-old with well wishes.
"Something with your head, you have to be very cautious with that," Posey said.
It was Banda's second Major League start.
"I hope for the best for him and I hope he has a speedy recovery if he is banged up a little bit," Banda said. "It's just something that got away from me."
As Bochy alluded to, Belt has had a history with concussions. If diagnosed as one, it would be the fourth (one in college and two in the Majors) of his career. Belt was hit in the face with a throw during batting practice in July 2014 and dove into second base and hit against an infielder's knee in September 2015.
Entering Friday, Belt had homered in two of the last three games. The career Giant leads the team with 63 runs, 18 homers and 48 extra-base hits.
"It certainly didn't look good," said starter Madison Bumgarner. "It was loud. I know it was a curveball, but it was really loud, it seemed like. Just hope he's all right."
Should Belt be sidelined for an extended period, infielder Ryder Jones could get some time at first base. Or the Giants could recall Jae-gyun Hwang, who was recently optioned, from Triple-A Sacramento. Posey could also play at first while Nick Hundley catches.
Added Bochy: "Our hope is this thing's going to be a lot better tomorrow."