Mark Teixeira and the Yankees had plenty to celebrate Friday. (AP)

NEW YORK — As Tuesday’s non-waiver trade deadline approaches, the landscape for the Red Sox is looking more and more difficult with each passing game.

The Sox lost for the sixth time in their last seven games, this time dropping a 10-3 decision to the Yankees in the teams’ series opener at Yankee Stadium.

The Red Sox fell to 49-51, marking the first time since June 15 they found themselves two games under .500, and pushing them 11 1/2 games in back of the first-place Yankees. Bobby Valentine’s club also came into the game 4 1/2 out of in the wild card race, with seven teams ahead of it.

The death blow for the Red Sox came in the eighth inning when Curtis Granderson took reliever Mark Melancon over the left field fence for a grand slam, marking the outfielder’s second such home run of the season (and 28th of the year).

Here is what went wrong (and right) in the Red Sox’ latest misstep:

WHAT WENT WRONG

- Mike Aviles was very slow turning what appeared to be an inning-ending, 4-6-3 double play off the bat of Mark Teixeira in the first inning. With the inning extended, not only did Curtis Granderson score the Yankees’ first run, but the prolonged frame allowed for Raul Ibanez’ two-run homer on the next at-bat. It made Ibanez 6-for-12 against Cook for his career.

- With nobody out in the third inning, Granderson’s grounder up the middle just eluded Cook and then snuck into center field thanks to miscommunication between Aviles and Dustin Pedroia. The play resulted in the Yankees’ fourth run when Teixeira brought in Derek Jeter with a sacrifice fly.

- A half-inning after the Red Sox crawled within a run, Russell Martin widened the gap once again with a long home run to left field, scoring Ichiro Suzuki and giving the hosts a three-run advantage.

- While Aaron Cook’s outing could have been a lot more painless if not for some shoddy fielding, it offered a much different vibe from what he had been delivering. The righty finished his four-inning outing giving up six runs on seven hits, including two home runs. It marked just the second time in the past two years the sinkerballer has surrendered multiple homers in a game.

WHAT WENT RIGHT

- Dustin Pedroia hit his second homer in as many games, launching a solo shot in the first inning to give the Red Sox a quick 1-0 lead. Seven of Pedroia’s eight homers have come with the Sox either trailing or tied.

- Carl Crawford hit a first-pitch home run well into the right field seats in the third inning, cutting the Yankees’ lead to a run. It was the outfielder’s first homer since Sept. 3, 2011.

- The third solo homer of the night for the Red Sox came from Jarrod Saltalamacchia, who took Hughes the opposite way for his 19th homer of the season. All but one of the home runs have come with Saltalamacchia hitting from the left side. The last seven home runs for the Red Sox have all been of the solo variety.

- Aviles made a nice play in the eighth inning, scooping out Martin’s slow roller in time to gun down Andruw Jones at home to keep the Yankees’ lead within three runs.

- After a subpar appearance, Frank Morales rebounded to pitch two hitless innings.