Braves shortstop Andrelton Simmons’ left thumb sprain is expected to keep him out of the lineup for no more than two games, so he didn’t have to learn another hard lesson about the risk of sliding head first.

It also means an early opportunity for Ramiro Pena to join the lineup after his strong play during the spring. It’s not the ideal situation for the Braves, but it’s not all bad.

“For me, it’s OK,” Braves manager Fredi Gonzalez said. “It’s just day-to-day and gives Pena a chance a little bit. We always talk about how good our team is, and one of my biggest challenges is playing everybody. And now Pena gets to play a little bit.”

Simmons injured his thumb while stealing second base during the third inning of the Braves’ 4-1 victory against the Cubs on Friday night at Turner Field. Simmons finished the game and originally was in Gonzalez’s lineup Saturday before getting scratched.

Simmons, who is batting leadoff for the Braves, said he jammed the thumb on second base while trying to avoid the tag. He said it swelled overnight and was painful, but tests confirmed that the strength is good.

“I feel good enough to go out there,” Simmons said. “If it was up to me, I would put myself in the lineup. But I guess they are trying to make the best decision for the team and for myself, I guess, so I understand.”

Gonzalez said he probably would hold Simmons out of Sunday’s series finale against the Cubs even if Simmons is cleared medically, just to be safe.

Simmons fractured his right pinkie finger while sliding head first into second base in July. He missed more than two months with that injury.

Gonzalez said players are warned frequently about sliding head first “but boys are boys.” Simmons said he doesn’t plan to change his slide.

“It’s just how I feel faster,” he said. “Maybe (I can) put something on my hand that makes it easier sliding, but I doubt if I plain just stop sliding head first.”

Upton hits lead-off: With Simmons out of the lineup, Gonzalez moved center fielder B.J. Upton from fifth to first in the batting order in an effort to shake him out of his poor start to the season. Upton was 0-for-14 with nine strikeouts in the first four games.

“He’s done it before,” Gonzalez said. “He’s not swinging the bat in the fifth hole, put him in the No. 1 hole. Maybe he gets some fastballs, get him on base, get him to think something differently.”

Before Saturday, Upton had 674 career at-bats in the leadoff spot.

Gattis' defense good, too: Braves rookie catcher Evan Gattis is off to a great start at the plate, with four hits in eight at-bats, including a home run in his debut. Gonzalez said Gattis also is coming along nicely behind the plate as he makes the transition to catching after doing it for only 17 games above the Single-A level in the minors.

Gonzalez said Gattis “put on a nice exhibition” blocking balls Friday. The manager also cited Gattis throwing out Dioner Navarro on a steal attempt at second base.

“We weren’t going to throw … (but) Navarro decides to (run), and (Gattis) came up and he saw that Simmons was covering, and he threw the ball and got him out,” Gonzalez said. “Most guys would not even throw. That’s a nice in-game decision, and you are surprised that a young player makes that.”