Watching from the dugout as Brian Roberts clutched the back of his right knee Thursday, Ryan Flaherty knew an injury to the Orioles’ starting second baseman could create an opportunity for him.

But Flaherty’s first feeling was concern for Roberts, a veteran teammate whom he says gave him invaluable advice as Flaherty manned second base for the Orioles in the playoffs last fall.

“It was tough to watch that, especially to have it happen to a player like him. He helped me tremendously last year playing second,” Flaherty said Saturday. “He’s been a great teammate. And to see him battle back then have a setback like this, it was tough.”

With Roberts sidelined for three to four weeks with the ruptured tendon in the back of his knee that he suffered in Thursday’s road win against the Tampa Bay Rays, Flaherty made his second straight start Saturday night against the Minnesota Twins. The second baseman batted eighth.

“Obviously, every time you get a chance to play, it’s exciting, just to come out and help this team keep doing what it was doing the first three, four games of the season, help the team win,” he said.

Flaherty batted .216 in 51 at-bats this spring with three home runs, four doubles and 10 runs batted in.

He went hitless in Friday’s 9-5 win over the Twins, but Orioles manager Buck Showalter wanted to give him another opportunity Saturday. Alexi Casilla will start at second base in Sunday’s series finale.

“We all know that Casilla runs better than Ryan. Ryan’s got a little more pop,” Showalter said when asked about their different skill sets. “I think they’re both good defenders. They both throw all right.”

Showalter indicated that he plans to give both players an opportunity to seize the starting spot until Roberts return. A strict platoon is a possibility, but Showalter is not guaranteeing that.

The Orioles optioned infielder Yamaico Navarro, who was called up when Roberts and was injured and who can also play second base, to Triple-A Norfolk before Saturday’s game to open up a roster spot for starter Chris Tillman. Navarro, a 25-year-old who was acquired in a trade with the Pittsburgh Pirates last November, did play in his short stint in Baltimore, batted .276 in 29 at-bats this spring with three doubles and four RBIs. He also drew six walks.

Flaherty, who hit .216 with six home runs and 19 RBIs in 77 games last season, knows he can’t take this next opportunity for granted as Roberts, his 35-year-old mentor, rehabs his way back.

“I felt like I had a pretty good spring,” Flaherty said. “But now is when it counts.”