SAN FRANCISCO -- A day before he watched Barry Bonds' number retirement ceremony while warming up in right field, Trevor Williams jokingly tweeted he was "slightly terrified" that Bonds might sign a one-day contract and start for the Giants on Saturday night.
But Williams breathed a sigh of relief when he saw Bonds wearing a suit and tie, not his No. 25 jersey, then handled San Francisco's actual lineup with ease. Williams allowed five hits, all singles, as he fired seven scoreless innings in the Pirates' 4-0 victory over the Giants at AT&T Park.
The Pirates now trail the Cubs by seven games in the National League Central, and they pulled themselves back within four games of the second NL Wild Card spot.
"We're in the Wild Card hunt, and we needed to get this win to at least split with the Giants this series. I knew it was an important game for us," Williams said. "It's amplified a little bit because it's sold out, they're there for Bonds, they're there for that number to be retired. It's amplified. It felt like a playoff atmosphere out there, and that atmosphere is fun to pitch in."
It was the continuation of an excellent run for Williams, who has permitted two runs in 29 innings over his last five starts. Williams has started seven of Pittsburgh's Major League-leading 13 shutouts this season, with four of those coming in his last five outings.
"It's a confidence thing. Every time you go out there, you have to trick yourself into thinking you're the best pitcher on the planet that day," Williams said. "I was on the field with the best hitter on the planet, and I was thankful he wasn't in the lineup tonight."
But Williams did struggle earlier this season. In nine outings before this five-start stretch, he allowed 37 runs in 41 innings. He intensified his work between starts, fine-tuning his focus and arm slot in search of more consistency. It seems to be paying off.
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Williams is not an overpowering pitcher, and his plan of attack is no secret. Of his 104 pitches on Saturday night, 87 were fastballs. He pounded the bottom of the zone with sinkers and went up in the zone with four-seam fastballs. He struck out two and walked only one batter, forcing the Giants to put the ball in play.
"It was a very impressive outing," manager Clint Hurdle said. "When he can get [his fastball] down there and live on the knees, there's some downhill angle to it as well. That's what's been impressive. He has elevated the ball really well. … He's done a really fantastic job with it."

The Pirates manufactured a run in the third inning to give Williams a lead. Josh Harrison drew a leadoff walk against Giants starter Ty Blach, advanced to second on a single by Jordy Mercer, took third on Williams' sacrifice bunt and scored on a sac fly by Corey Dickerson.
Josh Bell padded Pittsburgh's lead in the fourth. After Gregory Polanco bunted for a hit and David Freese reached on an infield single, Bell smashed a 2-2 sinker from Blach into the left-field seats. The 377-foot homer was Bell's second of the series, his second of the season as a right-handed hitter and his eighth overall on the year.
"I feel good. I feel strong," Bell said. "Just trying to get pitches elevated and do damage."

Williams finished the sixth inning having thrown 95 pitches, but he batted for himself and returned to start the seventh with reliever Edgar Santana warming up in the bullpen. But there would be no need for Santana to take the mound, as Williams breezed through a nine-pitch inning.
"You have to play up and pitch like you're the best pitcher on the field that day," Williams said. "It's tough when things are going bad, because that result isn't getting there, but it's also good when things are rolling and you believe that and truly feel that difference."
SOUND SMART
This was the Pirates' first shutout against the Giants since a 1-0 victory on June 20, 2016. The Bucs had not completed a shutout in San Francisco since winning, 5-0, on July 28, 2014.
YOU GOTTA SEE THIS
When he's on top of his game, Williams produces plenty of balls in play and quick innings -- a combination that keeps Pittsburgh's infielders on their toes then off their feet. It was on display in the seventh inning, when Austin Slater hit a 1-1 sinker that bounced off third baseman Freese's leg toward shortstop Mercer.
Mercer played the deflection perfectly, scooping up the ball and firing to Bell for the first out of the inning.

"I don't know if I would have been taken out [if Slater reached safely], but it's a single in the seventh up by four," Williams said. "Sometimes that's just the difference in the ballgame."
HE SAID IT
"It was weird warming up. I just felt like such a jerk out there while I was warming up before the game, but I had to do what I had to do to get ready for a game. It was definitely the most nervous I've been before a game just in terms of people [being] there for Bonds, and if I had one screw-up, I wasn't going to hear the end of it." -- Williams, on warming up in right field during Bonds' ceremony
UP NEXT
The Pirates will look to finish off a series victory on Sunday afternoon at AT&T Park with right-hander Joe Musgrove starting against Giants rookie Dereck Rodriguez. Musgrove allowed two runs (one earned) on four hits over seven innings in a loss at Coors Field on Monday. First pitch is scheduled for 4:05 p.m. ET.