Baltimore — A tense AL East duel between the New York Yankees and Baltimore Orioles revealed the strengths and weaknesses of each team.

After the Yankees beat the Orioles 6-4 in 10 innings Monday night to extend Baltimore’s losing streak to six games, it became apparent why New York leads the division and Baltimore is mired in its longest skid in nearly a year.

Both showed their hitting prowess. Both played solid defense. The difference was that the Orioles got another poor performance from the back end of their bullpen, and New York got a typically strong outing from closer Mariano Rivera.

New York trailed 4-3 in the ninth before Travis Hafner homered with one out on a 3-1 pitch from Jim Johnson, who has blown three straight save opportunities after converting a franchise-record 35 in a row. All three of those botched saves have come during Baltimore’s current slide.

Pedro Strop then gave up two runs in the 10th to complete the collapse. After that, Rivera breezed through a 1-2-3 inning for his 17th save in 17 tries.

“Believe me, I don’t take him for granted,” Yankees manager Joe Girardi said of Rivera. “It’s hard to do it year after year after year. You’re going to see guys go through some ups and downs, but Mo doesn’t go through a lot.”

Neither did Johnson until last week, when he blew ninth-inning leads against San Diego and Tampa Bay before collapsing against the Yankees.

“The ball’s up. That seems to be the common thing lately,” Johnson said. “Just not making the adjustment. I’m trying, you know, doing everything. I’m going to work through it.”

Rivera, on the other hand, has been darn near perfect. And that is why the Yankees are 28-16 and Baltimore is five games back, as close to last place as first.

The Yankees also improved to 19-0 when scoring first this season.

“All bullpens are going to go through their struggles,” Girardi said. “The bottom line is that we were able to get some runs off some pretty good pitchers tonight.”

Robinson Cano hit his team-high 13th home run in the first inning for New York, David Adams clubbed his first major-league homer in the second and Lyle Overbay connected in the seventh.

In the 10th, Ichiro Suzuki led off with a double off Strop (0-2) and Vernon Wells followed with an RBI double to left. Hafner added a two-out single to make it 6-4.

David Robertson (3-0) worked the ninth as part of a relief crew that allowed two hits and no runs in 3 2-3 innings. Their effort followed an uneven performance by starter CC Sabathia.

Asked to assess the bullpen’s performance, Sabathia said, “Unbelievable, but that’s just been all year. We knew that was a strong point of our team, but they’ve really carried us. They’ve been great.”

After Overbay put New York up 3-2 in the seventh with a homer off Troy Patton, Baltimore took the lead in the bottom half. Alexi Casilla singled and scored on a double by Nick Markakis, who came home on an opposite-field double to right by J.J. Hardy.

Orioles manager Buck Showalter elevated Hardy to the third spot in the lineup because the shortstop came in with a .321 career batting average against Sabathia. Hardy also doubled in the fifth against the big left-hander.

“We had the lead and it’s up to me to go out and shut the door,” Sabathia said. “It’s very frustrating, especially in a close game like this. Luckily, these guys were able to bail me out.”

Sabathia gave up four runs and 11 hits in 6 1-3 innings. He left with New York trailing 4-3, but Hafner’s shot in the ninth preserved Sabathia’s 17-4 lifetime record against Baltimore.

Orioles starter Freddy Garcia, who pitched the past two years for the Yankees, allowed two runs, three hits — two homers and a meaningless single — in six innings. Aided by two double plays, the right-hander faced only three batters over the minimum.

Cano and Adams provided the Yankees with a 2-0 lead before Chris Davis hit his 13th homer for Baltimore in the second.

After wasting a two-out double by Matt Wieters in the fourth, Baltimore pulled even in the fifth. Steve Pearce hit a leadoff double and scored on a single by Markakis. Later in the inning, Sabathia retired Adam Jones on a grounder with runners at second and third.

Replays indicated first base umpire Eric Cooper got two calls wrong in the sixth inning, both of which went against Baltimore. Brett Gardner appeared to be picked off first base and was called safe, and Wieters seemed to beat out an infield hit but was called out.

■ Orioles RHP Miguel Gonzalez (blister on thumb) will return from the disabled list Tuesday night and start against the Yankees, who will have right-hander Phil Hughes on the mound. Hughes yielded seven earned runs in the first inning of his last start, against Seattle. ... Yankees 1B Mark Teixeira batted in a simulated game in Florida, testing his injured wrist for the first time since spring training. Also, 3B Kevin Youkilis (spine) took batting practice and fielded ground balls; 3B Alex Rodriguez (hip surgery) fielded grounders; INF Eduardo Nunez (oblique) did dry swinging and also took grounders; and RHP Ivan Nova threw 60 pitches in extended spring training ... Washington Capitals forward Brooks Laich threw out the ceremonial first pitch. ... Suzuki extended his hitting streak at Camden Yards to 20 games.