The seventh-inning solo shot that just cleared the Green Monster capped his four-hit return to Fenway Park -- more hits than he had in any of his 130 games with Boston last year -- and lifted the Diamondbacks to a 7-6 victory over the Red Sox on Friday night.
"Obviously, I want to come in here and perform and play well. Anytime you play against one of your old teams, you want to do that," Ross said, "but I have no hard feelings toward anybody in this organization."
Ross, Boston's regular right fielder last season, drove in three runs, doubled twice and singled once. His big hit came with the score tied at 6-6 when he led off the seventh inning against Pedro Beato (1-1) with his seventh homer of the year. It barely made it over the left-field wall and the umpires upheld the call after a video replay.
"I thought I hit it pretty good, better than I did," he said, "but, nonetheless, they all count."
In his only season with the Red Sox, Ross hit .267 with 22 homers and 81 RBIs. But they let him leave as a free agent and signed Shane Victorino to take his spot in right.
His focus was greater in his first game at his old stadium.
"It feels like a playoff-type deal," said Ross, whose second-place team remained four games behind the Los Angeles Dodgers in the NL West. "You don't want to give away any at-bat. Maybe I should do that every time I go to the plate. I'd probably be a better player. But your concentration level's a little higher, a little more intense."
He doubled in the first, then singled in a run in the third, cutting Boston's lead to 4-3. He hit another RBI double in the three-run fifth when Arizona went ahead 6-4. He finished his night by grounding out in the ninth.
"He came back with a little bit of a chip on his shoulder. Ross is a good guy," Boston starter Jon Lester said. "But when he steps in that batter's box, he's just another hitter that I've got to get out. Obviously, I didn't do that."
Brad Ziegler allowed singles to Stephen Drew and Jacoby Ellsbury in the ninth, but got his sixth save in six chances by retiring the last two batters as the Red Sox barely missed their third walkoff win in three days. But they kept their one-game lead in the AL East over Tampa Bay, which lost to San Francisco, 4-1.
"We started to put it together," Red Sox manager John Farrell said. "Things started to build, a little momentum, similar to the feeling that we've had the last couple of nights. But, unfortunately, it didn't happen here tonight."
The Red Sox had tied the game at 6 in the sixth on Drew's two-run homer, his eighth of the year, after a single by Mike Napoli.
Randall Delgado (4-3) got the win despite his worst performance of the season. He gave up six runs in six innings, the first time in his nine starts this year that he allowed more than three. He entered the game with a shutout streak of 14 2/3 innings after tossing the first shutout and complete game of his career in his last start, a 10-0 win over San Diego.
Lester also struggled after a solid stretch in which he posted a 2.29 ERA in his previous three starts. In his last start before Friday, he pitched seven innings in a 5-0 win at Baltimore. But against the Diamondbacks he allowed six runs and 11 hits in a season-low 4 1/3 innings.
"If I knew why I was off, I would have made the adjustment a lot earlier," he said.
Arizona finished with 16 hits.
"That's the way we should be swinging the bats," Arizona manager Kirk Gibson said. "It's been a while. We came out and swung with some aggression."
Ross' RBI single scored Martin Prado, who had doubled in the third. Then the Diamondbacks took a 6-4 lead with three runs in the sixth on RBI doubles by Prado and Ross and a run-scoring single by Jason Kubel.
"I had this game circled on the calendar for a while," Ross said. "It was really nice to be back in Fenway."
Jack Peavy (8-4) makes his first start for Boston since being obtained from the Chicago White Sox when he faces Patrick Corbin (12-2) on Saturday night. ... Ortiz has reached base in 16 straight games. ... Arizona SS Gregorius struck out in all four at bats. ... J.J. Putz pitched 2/3 of an inning in relief of Delgado and held the Red Sox scoreless for the 13th straight game, starting in Aug. 26, 2006. ... Lester didn't issue a walk for the second time in three games.