Ellsbury, the Red Sox's leadoff man and centerfielder, went 2-for-4 with a three-run homer, a two-run single and a sacrifice fly in Boston's 10-4 victory over the Yankees at Fenway Park.
The career-best outburst -- his previous high in RBIs was three -- included his 19th homer of the season, a three-run shot to rightfield against CC Sabathia. With all the boppers in the Boston order, it's Ellsbury who is second to David Ortiz on the team in home runs. Ortiz has 21.
Ellsbury hit a third-inning sacrifice fly for the game's first run. His home run capped a five-run Boston fourth and put the Yankees in a 7-2 hole. His two-run single in the eighth off Hector Noesi made it 9-4.
"Tremendous day," Red Sox manager Terry Francona said. "The home run -- we've got two outs, we got two [runs] in the inning, then he hits a three-run homer and spreads it out. And off a guy like CC. That's pretty impressive."
Ellsbury has been impressive all year after playing in only 18 games in 2010 because of rib injuries. "A young, developing player," Francona said. "That was our biggest concern. He looked healthy . He certainly looked like he had a point to prove. But saying that and hitting .320 or .330 with a lot of RBIs is a difference. He's been tremendous and you can tell he's confident."
Said Ellsbury: "You want to be out there playing. You want to help the team win. That's what it's all about."
Ellsbury already had done that twice this past week. He had walk-off hits against Cleveland on consecutive days, including his first career game-winning homer Wednesday.
"He started out a little slow and he's been a really good player probably from the first of May," Francona said. "Then all of a sudden he got good and went to maybe great. He's kind of held that level."
Ellsbury, 27, has entered the AL MVP picture along with teammate Adrian Gonzalez. Ellsbury is batting .321 with 31 doubles, 19 homers, 72 RBIs and 31 stolen bases, and there still are 50 games to go. "I'm just enjoying being out there playing," he said. "We're winning ballgames. I'm just enjoying it."
Gonzalez, who went 1-for-4 Saturday, is batting .352 with 34 doubles, 18 home runs and 91 RBIs. He leads the majors in batting average and RBIs.
But the Red Sox aren't concerned about the MVP race. They're more concerned about the AL East race and the wild-card cushion both teams enjoy. The Yankees and Red Sox again are tied for first in the division and the wild-card race at 69-43.
"Our things are always to win series," Ellsbury said. "If we keep on winning series, in September, when we look back, we'll be in a great position."