BOSTON -- Defense was a huge key for the Red Sox in their three-game sweep of the Yankees at Fenway Park this week.

Boston's defensive prowess wasn't in just a bunch of meaningless plays, either. The leather that was being flashed in highlight-reel fashion that proved crucial, especially Thursday night.

It started in the top of the eighth inning with the Red Sox trailing by two runs. With one out and a runner on first, the Yankees' Melky Cabrera lined a shot to left-center field. It appeared to be a sure extra-base hit, and possible another run for New York.

Rocco Baldelli had other thoughts.

Boston's center fielder, in an all-out sprint in the wet and sloppy terrain, made a tremendous diving catch for the second out of the inning. The base runner, Hideki Matsui, was forced to retreat to first. Sox reliever Takashi Saito ended the inning by striking out Francisco Cervelli

Boston answered with three runs in the bottom half of the inning to take a 4-3 lead.

"I didn't know [if I had a chance off the bat]. [But it] was wet out there, and the closer I got to it, I figured I had a chance at it," said Baldelli. "But I didn't know for sure off the bat."

He did get to it, and it became a momentum swing for the Sox.

"It was like a water-park ride," he said of the dive he made in the rainy and wet conditions.

The Sox needed their defense again in the top of the ninth to hold New York at bay. This time it was shortstop Nick Green.

It just so happens the Red Sox are 25-9 when he starts at short, and his play to record the first out in the ninth may give a hint as to why. The Yankees' Derek Jeter hit a chopper up the middle off closer Jonathan Papelbon when Green quickly ranged to his left and snared the ball. His momentum was carrying him towards the outfield, so he spun and made a perfect throw to Kevin Youkilis to get Jeter by a hair.

"I don't know how many shortstops have made that play," said the manager. "It was a special play."

Green said after the game that the ball wasn't that wet because it only hit the ground a couple of times. Still, it was a spectacular play.

"Ball hit up the middle, it's a play you want to make. If he gets on, it raises havoc. So you're just trying to get the first out," said Green.

Red Sox second baseman Dustin Pedroia got a good look at it as he converged on the ball, too.

"That was awesome," said Pedroia. "Obviously, the ball was probably all wet, and Jeter runs well, so to get that leadoff guy out, that was huge for us. He's got a lot of range, and obviously a great arm too, so when he gets to it, it's going to be an out."

Baldelli's play put in motion the defensive momentum, and even he wanted to give all the credit to Green.

"It was such a well-played game on both sides that you need to make plays like that to win games like this," said Baldelli. "Just watching Green's play up the middle, off the bat I thought it was just a chopper up the middle. I had a pretty good view of it and I didn't think he had any chance, but when he spun and threw, I mean Jeter wasn't very far from first base when Green released the ball, and he made a good throw."

Papelbon did the rest and retired the next two batters to secure the 4-3 victory.

jmcdonal@projo.com