Yankees clicking, more no-no flirtation on interleague weekend

1. Yankees' starters streaking

The Yankees have won nine straight games, sweeping a trio of three-game series against NL East opponents: Mets, Braves and Nationals. This weekend's sweep was the most impressive, as the Yankees cooled down a first-place Washington team coming off an undefeated six-game road trip at the Blue Jays and Red Sox. New York now has a 1 1/2-game lead in the AL East and the league's best record.

There's no secret to the Yankees' recent success, either: It's all about the starting pitching.

Ivan Nova's 7 2/3 innings on Sunday and Andy Pettitte's seven innings on Saturday extended an incredible stretch during which New York starters have finished at least seven innings in 16 of their last 22 starts, dating to May 23. Overall, the staff has 29 starts of at least seven innings this season, fifth in the majors.

New York is 18-4 over this period, with its starters logging a 2.76 ERA and .243 average against. They've failed to complete six innings only once in that span, and all five have pitched well:

Hiroki Kuroda -- 3-0, 1.29 ERANova -- 5-0, 2.48Pettitte -- 2-1, 2.88CC Sabathia -- 3-1, 3.54Phil Hughes -- 3-0, 3.71

2. Near no-nos

There were no new additions to 2012's growing list of perfect games and no-hitters this weekend, but there were two close calls Saturday. The Orioles' Jason Hammel and the Angels' Ervin Santana each took a no-hitter into the seventh inning; both finished with a complete-game one-hitter.

Though Santana made an All-Star team in 2008, threw a no-hitter in 2011 and had a sparkling 3.38 ERA last season, his performance -- perfection through 6 2/3 innings -- was far more unexpected, given his rough season. He had given up seven runs in his two previous starts and took a 5.74 ERA into the outing. If he gets back on track for the rest of the season, the Angels, who have allowed the fewest runs in the AL (247), should have no trouble living up to their lofty preseason hype.

Hammel, meanwhile, credits a rediscovered sinker with his breakthrough season. He had a 4.99 career ERA before his trade to Baltimore this offseason, but he has gone 7-2 with a 2.87 ERA with career highs in K/9 (8.5) and groundball-to-flyball ratio (1.12), both of which are 20 percent increases over his previous single-season bests.

3. Trouble in Toronto?

No team had a worse injury week than the Blue Jays, who placed three members of their rotation on the disabled list: Brandon Morrow with an oblique strain and Kyle Drabek and Drew Hutchison with elbow strains. What was a team strength -- 4.08 starter ERA, fourth in the AL -- is now a great unknown. Though Toronto swept the Phillies this weekend, its staff after Ricky Romero and Henderson Alvarez must be reinvented.

A reinforcement may be on the way. FoxSports.com reported late Sunday that the Blue Jays have discussed trading for the Rockies' Jeremy Guthrie.

There is a strong correlation between a team's record and the number of starting pitchers it uses; the more starts by the original rotation typically translate to more success.

The Blue Jays had only used six starting pitchers this season until Sunday, and one of those six, Joel Carreno, only made one spot start April 8. Now Toronto needs to replace 60 percent of its rotation, though Sunday was an encouraging start (pun intended) as recently promoted Brett Cecil allowed only two runs over five innings to earn a win. (The Jays have yet to announce the other two replacement starters.)

Only two clubs, the Marlins and the Reds, have used the minimum five starters so far this season. Three teams have used a double-digit number of starters already: the Rockies and Royals have given the ball to 10 pitchers, while the Padres have employed 12.

4. Home run happenings

*Pirates third baseman Pedro Alvarez hit two home runs in Saturday's win over the Indians -- and then two more in Sunday's victory. Alvarez is the first player with back-to-back multi-homer games this season, but he's done it before: July 20-21, 2010. Only the Rangers' Mike Napoli has replicated the home-run barrage in the interim, having done so Sept. 27-28, 2011.

*There's no more surprising home run hitter this year than Trevor Plouffe, whose 14 homers in 46 games are more than the 10 career home runs he had hit in 103 previous games. Plouffe has hit 13 of his home runs since May 16 -- including two Friday as part of a stretch in which he homered in four straight games and six out of seven. In that same span, Minnesota has hit only 31 homers as a team, with none of his teammates having more than six (Justin Morneau and Josh Willingham).

*The Reds swept the Mets in three to extend their winning streak to five games -- but uncharacteristically did not rely on the home run. Cincinnati ranks second in the league in percentage of runs scored via the homer (41.8 percent) and is tied with Milwaukee for most times hitting three or more home runs in a game with 11. Nine of the Reds' three-plus homer games have happened since May 13 -- including Thursday's victory over the Indians -- during which time the club is 22-11 and has gone from 2 1/2 games back in the NL Central to leading by four games.

5. Extra, extra!

There were three extra-innings game Saturday and three more Sunday; that's 20.69 percent of all games those two days. Four of the six extra-inning games went at least 14 innings.

Despite the weekend surge, however, extra-inning games are actually at their lowest since 2006, at just 7.88 percent. It would seem reasonable to surmise that lower scoring might lead to more extra-inning games as ties would be hard to break, but that has not been the case so far this season even though it had appeared to be true in 2010 and 2011. Instead, extra-inning games remain random (at least as correlated with runs scored).