ATLANTA -- Braves left fielder Ronald Acuna Jr. is grateful that his knee and back injuries aren't as serious as he first thought.

"To be honest, I feel better than I did yesterday,'' Acuna said Monday through an interpreter. "I just give thanks to God it's not worse than it was.''

Atlanta placed Acuna on the 10-day disabled list with a mild ACL sprain in his left knee and bruises to his knee and lower back.

Acuna's leg buckled while running out a grounder Sunday in Boston. He fell on his back after crossing the bag, then rolled over on his front side with what looked to be a gruesome injury. The 20-year-old surprisingly walked off the diamond, declining a wheelchair.

"I thought his season was over when it happened and I went out there,'' manager Brian Snitker said. "Now it's very optimistic.''

Acuna, who is hitting .265 with five homers and 13 RBIs in 51 games, is walking without a brace and tried to talk his way into the lineup for the second game of a doubleheader before he was placed on the DL.

"Obviously, I have some pain, and it definitely feels sore and hurts, but I'm not worried about it,'' he said. "I know the pain's going to go away.''

Preston Tucker went 0-for-3 as he took Acuna's place in the field during the Braves' 4-3 win in the first game of a doubleheader against the New York Mets. Ozzie Albies, the usual leadoff hitter, batted in Acuna's No. 2 spot, and Ender Inciarte batted first. Charlie Culberson, who won the first game with a pinch-hit, two-run homer in the ninth, started the second game in left field.

The Braves selected the contract of outfielder Dustin Peterson to take Acuna's place on the roster.