"I was scared when I saw it," said Luis Gonzalez, who was standing at third base.
"It's a dangerous play," said Matt Treanor, the batter.
The Marlins have been a surprise all season, and they pulled off another one Wednesday night, using the brazen bunt to help end Webb's winning streak.
"I'm not going to go 33-, 34-0 probably," said Webb (9-1). "It was going to happen sometime. Losing in this manner, to a guy who pitched a great game, is probably a good way for it to happen."
Webb was bidding to become only the third pitcher since World War I to win his first 10 starts. Instead, he left for a pinch hitter after allowing six hits and three runs in seven innings.
"There's not going to be as much media around to be canonized -- that's probably the only good thing," Webb said. "I'm just going to have to go out in five days and try to get to 10-1."
Treanor's bunt made tied it 1-1 in the fifth inning, and Cody Ross followed with a homer. Stephen Drew hit his sixth homer for the Diamondbacks, but that's all the offense they could muster against Nolasco (3-3).
Florida won for the second consecutive night in the matchup of first-place teams. The NL West-leading Diamondbacks came into the series with the best record in the majors, but they have totaled three runs and 10 hits in the first two games against the Marlins, who lead the NL East despite baseball's lowest payroll.
"We still have a lot to prove," Luis Gonzalez said. "People are waiting to see if this is a legitimate team, and that's to be expected. It's a young team and a tough division."
Nolasco's performance was his best since his rookie season in 2006, when he won 11 games, and he lowered his ERA from 5.18 to 4.62. The right-hander said he drew extra incentive from facing Webb.
"You go out there and try to match a guy like that inning for inning," Nolasco said. "You know he's going to be good, and we've just got to try to be better. You've got to be on top of your game."
Webb retired the first 11 batters and took a 1-0 lead into the fifth, when the Marlins scored twice. Gonzalez tripled with one out, then took off on a 1-0 pitch as Treanor bunted up the first-base line.
"It's just one of those gut things," Fredi Gonzalez said. "It worked out. If it didn't work we lose 1-0, or we're still out there playing."
Gonzalez scored standing up as first baseman Conor Jackson fielded the ball and tagged Treanor.
"It's awesome, especially when you hear the crowd going wild as you're getting tagged out," Treanor said.
Ross then hit his fifth homer, pulling a 2-0 pitch over the scoreboard. It was only the third home run allowed by Webb this season.
Florida added a run in the seventh on Dan Uggla's double and a single by Gonzalez.
"With Webb it's riding one of those tough rodeo bulls," Fredi Gonzalez said. "You've just got to hang on."
Trailing 3-1, Arizona had runners at the corners with one out in the eighth, but Matt Lindstrom struck out Orlando Hudson and Jackson. Kevin Gregg completed the four-hitter with a perfect ninth for his second save in as many nights, and his ninth in 10 chances.
The Diamondbacks struck out 11 times.
"We were all hot at the same time," said Justin Upton, who is 0-for-7 in the series with five strikeouts. "And as it looks right now, we're all cold at the same time."
The exception is Drew, who homered to lead off the fourth and had three of Arizona's four hits.
The Marlins won without slumping shortstop Hanley Ramirez, held out of the lineup for the first time this season. Ramirez, who signed a $70 million, six-year contract extension Saturday, was 1-for-15 with 10 strikeouts in the past four games.
Orlando Magic coach Stan Van Gundy wore a Marlins T-shirt to the game and visited beforehand with Florida manager Fredi Gonzalez, a longtime friend. ... Over the past five games, the Diamondbacks are 1-for-40 the first time through the order with 14 strikeouts.