HOUSTON -- The Red Sox lost in more ways than one Thursday afternoon, dropping Game 1 of the American League Division Series presented by Doosan, 8-2, to the Astros and losing Eduardo Nunez to an aggravated right knee injury four pitches into the game. 
Nunez will be replaced on the Red Sox's roster by veteran outfielder Chris Young and will be ineligible to return for the AL Championship Series, should the Red Sox advance to the next round. Nunez could come back for the World Series if Boston makes it.
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Nunez had been limited to one regular-season game since suffering a sprained posterior cruciate ligament Sept. 9, but he started at the designated-hitter spot and took his first at-bat against Justin Verlander in the first inning. After tapping a grounder to third base, Nunez stumbled out of the box and then crumpled to the ground while running down the first-base line, his face contorted in pain.
Unable to put weight on his leg, Nunez had to be carried off the field by manager John Farrell and assistant athletic trainer Masai Takahashi. 
"It feels sore," Nunez said. "It's not right yet. I'm going to have another MRI in a few days and go back to Boston. But we don't see [more] damage so far. There's no swelling. It's just the same pain it was before -- a little more painful this time."
Nunez, 30, batted .321 with an .892 OPS, eight home runs and 27 RBIs in 38 games after the Red Sox acquired him from the Giants ahead of the non-waiver Trade Deadline. Thursday marked his second unsuccessful attempt to rush back from injury, as he also exited a game last week after two at-bats due to renewed discomfort in his knee.
"We tried to rush twice because we didn't have a lot of time," Nunez said. "We did a lot of tests. Obviously no one expected that. I thought I was a little more ready than what I am."

Still, Farrell said he did not regret trying to bring back Nunez for the postseason.
"He had been cleared prior to the start of this series," Farrell said. "The number of tests that we put him through felt like he had satisfied all that we could simulate, but it was apparent trying to go game speed we saw what transpired."
With Nunez out for the remainder of the series, the Red Sox will lean more heavily on Hanley Ramirez, who replaced Nunez as the designated hitter and went 2-for-3 with a double.