"He's -- surprisingly -- moving around relatively well," Green said. "I thought the way that it looked that it was going to be something that was fairly drastic. But he's walking around the training room doing deep knee bends and lunges.
"He's got a little swelling in the ankle, but I'm somewhat optimistic he avoids a DL stint with the way he's moving around right now."
Jankowski grounded an 84-mph slider from Marlins lefty Wei-Yin Chen to second baseman Derek Dietrich and immediately sprinted out of the box. Jankowski caught the front right edge of the first-base bag while lunging forward to reach safely, and his right ankle appeared to roll severely.
He went down after crossing the base for a few moments before being helped off the field. Reliever Luis Perdomo replaced Jankowski as a pinch-runner.
"I don't think he's in the lineup [Tuesday] or available [Tuesday], but we'll see where he is when he wakes up," Green said. "Sometimes the swelling 24-48 hours can blow up on you.
"But he's sprained that ankle pretty good a few times in his life and I think you get a little bit of laxity in it when you've done it a few times ... so he rebounds quicker than [if] it's the first time. So, we're hoping he's OK."
After Jankowski's infield single, he is hitting .250 (12-for-48) with a .357 on-base percentage. He's stolen five bases and has proven to be a solid glove in the outfield.
Carlos Collazo is a reporter for MLB.com based in San Diego. Follow him on Twitter @CarlosACollazo. This story was not subject to the approval of Major League Baseball or its clubs.