BAGSHOT, England -- Calvin Johnson is more encouraged about his progress this week in returning from a high right ankle sprain than he has been the past two weeks, when he has missed back-to-back games for the Detroit Lions.

Calvin Johnson has missed the past two games, but says his ankle is progressing in a "positive direction." Gregory Shamus/Getty Images

He practiced for the first time in two weeks on Wednesday, although on a limited basis, and said he has been moving better than in prior weeks. He was also able to practice Thursday.

"Good. We're doing everything from straight-forward running to moving laterally as well," Johnson said. "Things are going good. We're moving in a positive direction."

However, he said a decision on whether he'll play could go all the way to Sunday inside Wembley Stadium.

Lions coach Jim Caldwell said the most important thing to see is how Johnson responded Thursday. But Caldwell said the decision will come down to doctors.

Johnson injured the ankle in the fourth quarter against Green Bay in Week 3 and then aggravated it in Week 5 against Buffalo, knocking him out for the past two weeks.

And while he is running on it and practicing again, he hasn't tested it too much. That, he said, will likely have to happen before he would consider playing Sunday against Atlanta.

"You want to push it. I want to push it, but we're trying to be smart about it," Johnson said. "Trying to take advice from the training staff that they are giving me and go with that."