TORONTO — Joe Girardi and Joba Chamberlain saw a step forward last night in the pitcher’s second straight short start, but progress, like beauty, is in the eye of the guy doing the looking.
In an effort to limit the right-hander’s innings and ensure his right arm is sound for years, the Yankees have skipped Chamberlain for significant stretches twice and used him for just three innings in each of his last two starts.
Chamberlain said his arm feels great, so judging by that, the plan is working. Looking at the math, however, tells another story.
Pitted last night against a lethal Roy Halladay, who allowed just one hit in pitching a complete-game shutout, Chamberlain gave up three runs (two earned) and six hits in three frames and absorbed a 6-0 loss which ended the Yankees’ win streak at seven games.
Halladay (14-8) retired the first 14 batters, walked Jorge Posada with two out in the fifth and gave up a one-out double to Ramiro Pena, the No. 9 hitter, in the sixth, pleasing the Rogers Centre crowd of 22,179.
Halladay was 2-4 with a 4.93 ERA in six starts since the July 31 trade deadline expired, and he still was a Blue Jay after a month of strong speculation he would be dealt. It was his second complete-game shutout this year and the 13th of his career.
Having the win streak stopped didn’t cost the Yankees ground in the AL East, where their lead over the Red Sox, who lost to the White Sox 12-2, remained at 7½ games.
Chamberlain said he saw progress last night, when he pitched to 19 batters in the his three innings of work.
“I was more aggressive with the fastball,” Chamberlain said.
“I know his numbers don’t show it, but he was more aggressive with his fastball,” Girardi said of his No. 4 starter, who likely will be shifted to the bullpen for the ALDS because the Yankees will only need three starters due to days off after Games 1, 2 and 4.
Girardi avoided speculating whether Chamberlain, who hasn’t won since Aug. 6 and hasn’t pitched well since July 29, would be part of his playoff rotation.
“I don’t want to talk about that yet,” Girardi said. “If we are fortunate to get to a seven-game series, we are going to need four starters.”
Because Sergio Mitre is the other option, Chamberlain will be the fourth starter if healthy.
Always the optimist, Girardi insisted Chamberlain will improve as he gets built back up.
“We have to get him back to where he was after the [All-Star] break,” Girardi said. “This isn’t going to last forever.”
Halladay has dominated the Yankees seemingly forever. He is 17-6 against the Yankees.
“He had all four pitches,” said Eric Hinske, who didn’t help Chamberlain in the first inning when he jumped for Aaron Hill’s fly to right and had it glance off his glove for a double. “He threw a lot of change-ups which is out of the norm. Another pitch in his arsenal isn’t good for us.”
Trailing, 5-0, in the sixth, the Yankees loaded the bases with two outs, but Halladay used a 90-mph cut fastball to freeze Alex Rodriguez on a 1-2 pitch to strand three.
“We lost, that’s the bottom line,” said Pena, whose fielding error on a routine grounder in the first led to one of the Jays’ first two runs being unearned. “I was just trying to get a good pitch to hit.”
As for Chamberlain, he needs to not only increase his innings — something he will do in the next outing — but pitch better. In his last six starts, he is 1-3 with a 7.96 ERA and has allowed 37 hits and 18 walks in 26 innings.
“There is a lot of baseball left, enough time to get going,” Chamberlain insisted. “I am not that far off.”
george.king@nypost.com