Santana has experienced ankle soreness since July 6, when Cubs outfielder Reed Johnson stepped on Santana's ankle in a race to first base at Citi Field. Six of the next seven batters reached base against Santana, and he allowed 17 earned runs in the next 8 2/3 innings, permitting 21 hits, walking five and striking out seven.
"The ankle issue is bigger than anybody has realized," said manager Terry Collins. "As we had gone back, ever since he's had the ankle injury, basically his command hasn't been there. We don't think he can land properly. He's using all arm to pitch, causing some fatigue in his shoulder -- no pain. We're going to give him some rest, let the ankle heal up, and rebuild the arm strength a little bit."
General manager Sandy Alderson expects Santana to take more than the minimum 15 days to recover, loosely targeting an Aug. 7-12 homestand against the Marlins and Braves for his return. Alderson does not believe there is any structural damage to the ankle, but said doctors will take another look at the shoulder that caused Santana to miss all of last season after he underwent surgery on Sept. 10, 2010.
Alderson reiterated, as Santana did after allowing six runs in three innings against the Dodgers on Friday, that there is no connection to the 134 pitches Santana threw in a June 1 no-hitter against the Cardinals. There is no shoulder soreness, just a lack of energy stemming from the ankle injury, which puts more pressure on his arm.
"Johan, I think, has exhibited the effects of 100 innings and a sore ankle for the last couple starts, and we think the ankle injury may have led to some general fatigue," Alderson said. "In light of the [shoulder] surgery and where he's been and what he's accomplished, we've gotten to the point where he needs to get that ankle right and get back to the point where he feels confident about pitching."
Santana said immediately after the ankle injury that it had no impact on his struggles, and he said on Saturday he would continue to pitch if it were his choice. But he acknowledged to Alderson, Collins and the training staff in a Saturday morning meeting that he still felt soreness.
"A couple times I felt it, but I don't think about it," Santana said. "When you're competing, you don't think about those things; you just want to get those guys out. When you watch the videos and review things, and what's going on with the pitches, you realize not everything is right."
The ankle affected Santana's command foremost. But it also affected his velocity, already down this season after he spent all of last season rehabbing his shoulder.
"He said that there's no energy," Collins said. "There's times when it's all work just to make the pitch. He said last night during the game he was really going to try to throw one hard, and he looked up and the velocity wasn't what he wanted it to be. That's when he said, 'I'm just tired.' It's all gone back to when he got stepped on."
Steven Miller is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.