Jonathon Niese is happy with his new changeup.

Niese allowed six hits — all singles — in 5 1-3 scoreless innings Saturday as the Mets lost to an Atlanta Braves' split squad 3-2.

"I felt good," Niese said. "I want to go out there and pound the zone and throw strikes with all my pitches. I got to use some changeups in situations that were 1-2. Some worked, some didn't. All-around it felt good."

Niese struck out three, walked none and hit a batter — Braves starter Kris Medlen. He threw 49 of 72 pitches for strikes and induced two double plays, both times with sinkers.

"It's pretty amazing — six innings, all six leadoff hitters got on and he pitched a six-inning shutout," Mets manager Terry Collins said. "You'll find that very seldom. It was an outstanding job. He mixed up all his pitches and really pitched good."

Niese, 11-11 with a 4.40 ERA last season, used his changeup in different counts, including the first pitch of at-bats. He said at times he threw the changeup away to let hitters know he had it, then came back with a four-seam fastball inside.

"The biggest thing with pitching is being confident with your pitches, trusting your pitches and right now I really trust my stuff," Niese said. "That helps me know that I can just pound the zone."

In three spring training starts, Niese has a 2.61 ERA in 10 1-3 innings with nine strikeouts, nine hits and just one walk.

"I think it's time for Jon Niese to step into what everybody thinks he's going to do and that's be a big winner in the big leagues because he's got the stuff," Collins said. "He's certainly has as good stuff as there is in this league."

While Niese has a spot in the Mets' rotation, Medlen is expected to work out of the bullpen for the Braves. After missing almost all of last season recovering from elbow-ligament replacement surgery, the 26-year old gave up one hit in four shutout innings, struck out four and walked one.

Medlen had thrown just two innings in each of his first two outings.

"I just wanted to keep the pitch count down, throw strikes and get ahead of guys," Medlen said. "I have no hesitation at all, no restrictions. My confidence is pretty high right now, but I'm still pitching exactly the way I used to. I'm attacking hitters and being aggressive and letting my fielders work."

Daniel Murphy had two hits, including a two-run single in the sixth against Sean Gilmartin. David Ross hit a go-ahead, two-run double in a three-run eighth inning off Ramon Ramirez that also included Matt Diaz's RBI single.

Martin Prado, Jason Heyward and Ross each had two hits for the Braves. Heyward also stole a base.

BRAVES 5, BLUE JAYS 3: Dan Uggla appears to be on track for a much better start this season, and Brandon Beachy is getting closer to being ready for opening day, too.

Uggla homered in his third straight game and Beachy struck out six in four innings while giving up two hits as the Atlanta Braves defeated the Toronto Blue Jays 5-3 in a split-squad game Saturday.

Uggla, who didn't play Friday, connected with a man on in the sixth inning off Blue Jays prospect Deck McGuire and is batting .310 with four homers and nine RBIs this spring.

The second baseman had been known as a notoriously poor spring hitter and his struggles carried over to the first half last season, his first year with the Braves. That's why he brought a new mindset to camp this year.

"I want to be aggressive. I'm not just going up there with the idea of just watching pitches," Uggla said. "I was too passive before. Now if I get a fastball, I'm attacking it. I changed my whole approach. I don't know why it took me so many years to figure it out."

Uggla began last season in a slump that lasted nearly three months. But he then put together a 33-game hitting streak and ended the year with a career-best 36 homers.

"I'm glad he's on our side," Beachy said. "He's crushing the ball."

Beachy was 7-3 with a 3.68 ERA and ranked second among rookies in the majors last season with 169 strikeouts. But he had trouble making it past the sixth inning because of high pitch counts.

By throwing more strikes, Beachy hopes to work longer into games for the Braves this season, and his third spring outing was encouraging.

"It was definitely a step in the right direction," the right-hander said. "I never let my control leave me."

Beachy had walked five in his previous start and came in with a 9.00 ERA. But he walked only one and the Blue Jays' run against him came after a popup to shallow left field ended up a triple.

"I felt much more comfortable," Beachy said. "I threw some good ones with all my pitches."

Chipper Jones and Michael Bourn each had two hits for the Braves. Catching prospect Christian Bethancourt also had two hits. Rookie shortstop Tyler Pastornicky drove in a pair of runs with a sacrifice fly and a single.

The other Atlanta squad also won, beating the Mets 3-2 in Port St. Lucie as Kris Medlen allowed one hit over four scoreless innings.

NOTES: Mike Minor, who hasn't allowed a run in three spring starts, will pitch for the Braves on Sunday against Baltimore. . Braves shortstop Jack Wilson (calf) is making progress in his rehab and hopes to avoid starting the season on the disabled list. He hasn't played this spring. . Infielder Josh Wilson (hamstring) may be available to play for the Braves as early as Sunday. He has been sidelined since March 7. . Tom Glavine and Gene Garber will serve as Braves guest instructors next week. Glavine is scheduled to arrive on Sunday and Garber on Monday.