PHOENIX -- Madison Bumgarner thought about this moment, because all pitchers do. He probably thought it would last more than four innings, though.

Bumgarner was pulled in the fifth inning of a 9-8 win over the Arizona Diamondbacks on opening night, and it wasn't an easy decision for manager Bruce Bochy. With two runners in scoring position and one out, Bochy felt he needed a spark, so he turned to Gregor Blanco.

"I was caught in a hard spot," Bochy said. "I hate to take (Bumgarner) out in that situation, but down three, I felt we had to do something. Finally, it started clicking."

It clicked too late for Bumgarner to pick up his 50th career win, and truth be told, Bumgarner probably went to sleep Monday night thinking he didn't deserve it anyway. He's the ace now, and he feels responsible on nights like this. When the guys behind him made a hot mess of the top of the fourth, Bumgarner couldn't stop the bleeding. Aaron Hill's double made it a four-run frame.

"I had a chance to get it out of it," he said. "Unfortunately I didn't. I feel like I did a great job of containing nerves. I felt really relaxed. I was able to control it enough where none of the hoopla bothered me. But my command was a little erratic. Arizona is not the easiest place to pitch."

It's because of that last part that Bochy felt he could make the move. The Diamondbacks struggle to pitch here, too, and Bochy wanted to start a rally. Bumgarner didn't fight him, even when he found out the bat was being taken out of his power-hitting hands.

"It was a tough decision," Bumgarner said.

His first career opening day start was a no-decision, but there probably will be more openers for the 24-year-old. Plus, there are these numbers: 0.00 (his ERA) and 1-0 (the team's record).

"That wasn't quite the way I drew it up," Bumgarner said, smiling. "But however we get the win, I'll take it."

  • It was a weird night for Brandon Belt, one that started miserably but ended with three hits, a homer and a joyous jog around the bases as Buster Posey's homer headed for someone's chicken finger plate. Two years ago, the Giants were a mess defensively as they got swept here during the opening series. Tonight, the infield again was a step late on just about everything. To be fair, I've been told that the infield here is pretty much like playing on a paved parking lot.

    "It's different, but we have to be aware of that," Belt said. "We're professionals. It's a little harder than most places, but we knew that. It shouldn't be an excuse for us."

    The Giants will need to lock it up defensively, Belt included. But he's already locked in at the plate.

  • On Day 1, we had no replay challenges. Bochy said they looked at the play at second when Brandon Crawford's foot came off the bag, but determined that the runner was safe.

  • Late in what was a rough spring for Jean Machi, the right-hander walked around the clubhouse dancing to an old-school hip hop song. You can see now why Machi was in such a good mood -- Bochy has a ton of confidence in him, and Machi was well on his way to making the opening day roster despite some shaky outings. Bochy waited on the top step after the top of the eighth to greet Machi, who was downright filthy in 1 2/3 innings. Machi got Paul Goldschmidt and Mark Trumbo swinging in the eighth. In this division, that's a hell of a way to keep your job.

    "He settled down and made some great pitches," Bochy said. "Machi has got that ability. He throws hard and he's got three pitches to work with."

    Said Posey: "He kept us within striking distance."

  • Speaking of valuable bench guys: Ehire Adrianza. The rookie had a hell of an at-bat in the four-run seventh inning and then put down a tricky tag on the inning-ending double play.

    "I was happy for the kid," Bochy said of the double. "That's pretty impressive."

  • It will be interesting to see how many complete games Michael Morse plays this season. Bochy wanted a fifth outfielder so that he could pull Morse in the late innings of close games, and after Morse struck out to end the top of the seventh, Bochy double-switched Juan Perez into the game. This is also why it always made sense for Perez to be that fifth guy; Bochy burned Blanco early but still had a really strong defensive outfielder on the bench.

  • That ninth-inning shot was the first homer Sergio Romo has given up to a Diamondback since 2010. Posey's homer was his second career blast with the score tied in the ninth inning or later (he hit a walk-off against the Dodgers last season).