MIAMI — After the way that Randall Delgado pitched Wednesday night, the Braves would certainly have to think long and hard before moving the rookie out of the starting rotation.

Delgado retired the first 12 batters in order and allowed only two hits and one run in 6 1/3 innings of a 2-1 win against the Miami Marlins, his second win during a six-game stretch in which Braves pitchers have reasserted themselves and helped get the team back on track.

Delgado (4-5) had a career-high seven strikeouts with one walk and also had the game-winning RBI on a fourth-inning single.

"Delgado gave us a hell of an outing, then we retired the last eight batters," said manager Fredi Gonzalez, whose Braves have won five of six since ending an eight-game losing streak.

Relievers Jonny Venters, Eric O’Flaherty and Craig Kimbrel set down the last eight Marlins in order, with Kimbrel collecting his league-leading 17th save in 18 chances.

The Braves hope it wasn't a costly win as first baseman Freddie Freeman left the game with an injured left index finger (his throwing hand) after being hit by shortstop Jose Reyes' relay throw sliding into second base in the two-run fourth inning.

Freeman had the finger in a splint after the game and will have it X-rayed and examined by a hand specialist on Thursday (there was no X-ray machine installed yet at new Marlins Park).

"Finally started to feel good with my eyes," said Freeman, who missed most of a week with vision problems. "Then seven or eight at-bats later this happens. It's been an up-and-down season. Hopefully it's not bad, just a bruise. Hoping for the best."

The Braves will go for a series sweep of the Marlins on Thursday night when struggling Mike Minor faces Miami veteran Mark Buehrle in a matchup of left-handers. The Braves pulled even with Miami, which was tied with Washington for first place in the National League East two days ago.

Delgado left a strong impression with the Marlins and manager Ozzie Guillen, who saw Marlins veteran Josh Johnson (3-4) pitch a fine game but get outshone by the Braves rookie.

"You’ve got to give credit to people who deserve credit," Guillen said. "I think Delgado, if I'm not mistaken and all due respect to other people we have faced in the past, I think this kid is the best one we have seen so far. He’s not the best pitcher we see but today he may have had the best stuff we’ve seen. And we faced some quality pitchers. I think this kid was at the top of his game. And the bullpen did a tremendous job. They’ve got a great bullpen."

Delgado has won both his starts in the Braves’ 5-1 resurgence, after going winless in his previous seven.

"I've just tried all year to make good pitches down in the zone and be ahead of hitters," Delgado said. "We got the win tonight for the team. We had good defense, and I'm going to give the credit to [catcher] Brian McCann for calling a good game."

Braves pitchers have a 2.38 ERA over the past six games, after posting a 5.66 ERA during the eight-game skid. Atlanta’s team batting average is over .290 during the 5-1 surge, up from .178 during the losing streak.

"He was nasty," Prado said of Delgado. "Both pitchers had everything going. It's good when you face an ace on the other team and your pitcher becomes an ace, like tonight. As soon as I saw the first inning, with the 95 [mph fastballs] and the movement, I thought, it's going to be tough night -- for both teams.

"[Delgado] is starting to understand hes' got so much talent to be a good pticher and step up."

Freeman had an RBI single in the two-run fourth inning, then was hit by Reyes’ relay throw on a Jason Heyward grounder. Freeman was called out for interference on the play and Dan Uggla had to go back to third base on what was ruled a double play.

"I slid normal and he came with a sidearm throw," Freeman said. "I couldn't believe that [umpire's] call. I slid normal. I wasn't trying to interfere with my hand or anything."

Delgado followed two batters later with a single through the left side on a hit-and-run play as Reyes went to cover second base. McCann led off the inning with a double, the second of the Braves catcher’s three hits (half of the Braves' total).

Delgado threw only 80 pitches (50 strikes) and was replaced after walking Giancarlo Stanton with one out in the seventh inning.

Gonzalez opened himself up to second-guessing by replacing Delgado after so few pitches and bringing in Jonny Venters, who had the worst month of his career in May. But the lefty came through, striking out Logan Morrison before coaxing an inning-ending fly ball to preserve the Braves’ 2-1 lead.

Delgado was perfect through four innings before hot-hitting Stanton led off the fifth with a double. But instead of having the inning spiral like Delgado’s had happen in some other outings, he got the next on a fly out and a ground out.

Bryan Peterson’s single to left scored Stanton to cut the lead to 2-1 before third baseman Martin Prado made a strong play on a John Buck grounder, charging in to field the ball and throwing to first while falling forward for the inning-ending out.

In the next inning, Delgado struck out the side in order, including Reyes and Omar Infante, to give him a new career high for strikeouts.

Minor has struggled mightily (2-4, 6.98 ERA) and could be replaced soon in the rotation. The Braves have Kris Medlen building arm strength at Triple-A Gwinnett in preparation for a move to the starting rotation when they were getting erratic performances from the back end of the rotation.

Delgado has made significant progress in recent weeks, while the same can’t be said for Minor.

Although Delgado drew a lot of criticism after giving up a second grand slam in a four-week span May 19 against Tampa Bay, the right-hander had a respectable 3.60 ERA and .230 opponents’ average in six May starts. The Braves scored two runs or fewer while he was in the first five of those, then scored five while he was in the game during his May 29 win against St. Louis.