Dan Haren, the good starter, pitches Dodgers to 2-1 win over Arizona

Dan Haren can be a confounding starting pitcher, which, I suppose, makes him the perfect pitcher for these Dodgers.

Haren is undergoing a slightly bizarre season, going on a series of conflicting streaks. He started the year 4-0 with a 2.39 earned-run average in his first six games, then went 4-9 with a 5.76 ERA in his next 16, and now, finally, is 4-1 with a 2.04 ERA in his last six.

He continued with the “good” Haren on Friday night, pitching the Dodgers to a 2-1 victory over the Diamondbacks before a Dodger Stadium crowd of 43,074.

The victory maintained the Dodgers’ two-game lead over the San Francisco Giants in the National League West, with 21 games left in the season.

Haren went six innings against Arizona, holding the Diamondbacks to one run on four hits and a walk. He struck out six. He was pretty much in control all night.

Combine all those good starts with the bad, and Haren is now 12-10 on the season with a 4.17 ERA. Which most teams would gladly take for a back-of-the-rotation starter.

The Dodgers needed Haren to be very good because they did very little with Arizona starter Vidal Nuno. And what little they did do came early.

The Dodgers opened the scoring with a run in the second inning after A.J. Ellis walked and Haren singled. Struggling Hanley Ramirez singled for the first of three times Friday to score Ellis.

Matt Kemp led off the third inning with an opposite-field homer to give the Dodgers a 2-0 lead. It was Kemp’s 18th home run of the season, one behind team leader Adrian Gonzalez.

Nuno then retired 14 consecutive Dodgers before walking Yasiel Puig with two outs in the seventh inning and giving up another single to Ramirez.

Nuno, acquired in July from the New York Yankees for Brandon McCarthy, looks like the original hard-luck loser. In 11 starts for the Diamondbacks he has posted a 3.16 ERA but is 0-5.

Pedro Baez took over for Haren and retired the only four batters he faced. Baez is looking like someone the Dodgers would want on their postseason roster. In his last 12 games, he has given up just one run.

Kenley Jansen came back from a rare blown save in the Dodgers’ game Wednesday to hold the Diamondbacks scoreless in the ninth inning and pick up his 40th save.