The Braves optioned relief pitcher Edgar Santana to Triple-A Gwinnett to open a spot on the active roster Sunday for starter Ian Anderson.

Santana is 3-0 with a 3.82 ERA in 36 games for the Braves this season, including a 2.78 ERA over his last 20 appearances dating to June 16.

He could rejoin the team after the MLB roster limit expands from 26 to 28 for the final month-plus of the regular season on Wednesday.

The Braves acquired Santana, a 29-year-old right-hander, from the Pittsburgh Pirates for cash on April 8. He made his Braves debut on April 30.

Anderson was activated from the injured list to start Sunday’s game against the San Francisco Giants at Truist Park, his first major-league game in seven weeks. He had been on the IL since the All-Star break and made four starts for Gwinnett on a rehabilitation assignment this month.

The return of Anderson gives the Braves six starting pitchers, rather than the normal five, on the current active roster. With no off-day until Sept. 6, manager Brian Snitker said it’s possible the Braves will use a six-man rotation this week, but he hasn’t committed definitively to that course.

“We’ll just see,” he said. “With lack of off-days, we have the ability to do that.”

Another option, he said, would be for Touki Toussaint to be shifted from the rotation to the bullpen. “That’s what we talked about doing down the road,” Snitker said. “He’s not going to be away from starting so long that he couldn’t go out there and throw seven innings.”

Toussaint pitched the ninth inning of Sunday’s 9-0 win over the Giants, basically to get in some needed throwing, but that doesn’t affect his usage later in the week.

“It worked out perfect to get him an inning today,” Snitker said after the game.

Outfielder Eddie Rosario comments on his first start with Braves and how he hopes to earn playing time in crowded outfield.

Braves notes

-Veteran outfielder Eddie Rosario, acquired from Cleveland at the July 30 trade deadline and activated from the injured list Friday, got his first start for the Braves in Sunday’s game. He played left field as Adam Duvall received a day off from the starting lineup. Rosario delivered two hits in four at-bats, including a two-run triple. Duvall, who previously had started all 25 games since the Braves acquired him from Miami on July 30, appeared as a pinch-hitter and lined out.

-Through Sunday’s game, Duvall ranked second in the National League in RBIs with 87 and was tied for third in home runs with 28 despite a .222 batting average. Those totals include six homers and 19 RBIs and a .196 average with the Braves.

-Huascar Ynoa has lost his past two starts, but his performance in those games against two of baseball’s elite teams, the Yankees and Giants, encouraged Snitker. “These are good lineups he’s facing, really good lineups,” Snitker said. “He can hang in there, I think, with anybody in the game, really. There is a lot of upside and a lot to like about this guy.” Ynoa allowed three runs on four hits in six innings (nine strikeouts) against the Yankees on Aug. 23 and two runs on three hits in six innings (three strikeouts) against the Giants on Saturday. He said those starts have been good for his confidence.

-By going 5-for-12 in the series against the Giants, Austin Riley raised his batting average to .304, tied for fourth-highest among NL qualifiers. He is hitting .359 since the All-Star break. He’s tied for third in the league (with Duvall and others) in home runs with 28 and has a chance to join Eddie Mathews, Chipper Jones and Bob Horner as the only third basemen in Braves franchise history to hit .300 with 30 homers in a season.

-The Braves fell from No. 15 at the start of the season to No. 23 last week in rankings of baseball’s 30 farm systems by MLB.com’s “MLB Pipeline.” The decline stems in part from the graduation of Anderson from prospect status and a drop in the stock of outfield prospects Cristian Pache (down from No. 12 to No. 40 in Pipeline’s individual “top 100″ rankings) and Drew Waters (down from No. 35 to No. 85).