DENVER — When B.J. Upton and Justin Upton hit back-to-back homers in the fifth inning of the Braves' 10-2 win Tuesday, capping a doubleheader sweep against Colorado, the brothers did something no others did in a major league game for three-quarters of a century.

Hall of Famers Lloyd and Paul Waner, famed “Little Poison” and “Big Poison” of the 1938 Pirates, were the only brothers to previously hit consecutive homers in the same inning, according to the Society for American Baseball Research.

“He had me excited about his good swing,” Justin said of his older brother, “then I got a good pitch to hit, too.”

It was his major league-leading 11th homer and second of the doubleheader, giving Justin a new Atlanta franchise record for home runs in April. The previous record was 10, twice by Andres Galarraga and once by Ryan Klesko.

The Braves hit three homers in the nightcap and three in a 4-3 win in the first game. The entire doubleheader was played in sub-freezing temperatures, including a record-breaking 23 degrees for the first pitch of the day and 27 degrees at the last pitch nearly 8-1/2 hours later.

"We got both games in, we swung the bats well," said manager Fredi Gonzalez, whose Braves lead the majors with 35 homers – no other team has 30 – and have a 15-5 record that's also the best in either league and five games ahead of the defending NL East champion Nationals (10-10).

In the second game, rookie Julio Teheran (1-0) pitched seven sharp innings for his second major league win and first career quality start in eight tries. He allowed eight hits (all singles) and no walks with three strikeouts, and threw 70 strikes in 90 pitches, including a six-pitch inning after the Braves took a 3-1 lead with a three-run fourth.

“I never pitched in weather like this before,” the Colombian said. “It was really cold the whole game. But I was trying not to think about it. I was trying to concentrate on my pitches, some things I did in the start before, like trying to get ahead in counts.”

Six Braves had two hits apiece in the nightcap including second baseman Ramiro Pena, catcher Gerald Laird, third baseman Juan Francisco, and right fielder Jordan Schafer, none of whom started the first game of the day.

Francisco hit a mammoth two-run homer in the fourth inning, and the Braves provided more run support for Teheran on the Upton homers to start the fifth and B.J. Upton’s sacrifice fly in the sixth.

The Braves have won all four of Teheran’s starts this season and scored six runs in each of the first three before blowing the lid off with 10 Tuesday. They scored more runs in Tuesday’s second game than in their last five games combined before Tuesday, including four losses.

That 1-4 stretch followed a 10-game winning streak, and the Braves’ were eager to get back on track after losing the last three in a four-game series at Pittsburgh to start a 10-game trip that will finish this weekend in Detroit.

“Coming off of three losses in Pittsburgh, that definitely wasn’t fun,” Justin Upton said. “So to come out here and do what we did today with the conditions, not give away at-bats, get pitches to hit and put some hits together – that can boost us.”

Just has done plenty of that himself in his first month with the Braves. He hit .307 with a .391 on-base percentage and majors-leading .813 slugging percentage in 20 games through Tuesday. He never envisioned getting off to such a torrid start after being traded from Arizona to Atlanta in January.

“You come into a season with a new team trying to fit in, just trying to be a part of a team that was already good,” he said. “I can’t put a thumb on it for why I’ve hit the way I have, but I’ve just to continue to work and keep it up.”

The No. 3 spot in the Braves lineup was occupied by now-retired Chipper Jones for most of his storied 19-year career. Now it belongs to Justin Upton, and isn’t expected to change anytime soon. He’s signed through 2015.

“For me, Justin is your No. 3 hitter,” Gonzalez said. “It doesn’t matter who’s on the mound that night, he’s No. 3 and he fills that void. Boy, oh boy, has he had a great April so far.”

After Francisco homered off Rockies starter Jon Garland (2-1) in the fourth inning, the Uptons pummeled Garland with back-to-back jacks. B.J. hit a 390-foot homer to left field to start the fifth and Justin hit a 422-foot drive to right on the next pitch.

The Braves have a 14-3 record against the Rockies since the beginning of the 2011 season, and have out-homered them 28-10 in that period.

Frustration among Rockies fans seemed to boil over a bit in the ninth inning, when a group of Braves fans behind their third-base dugout stood and did the war chant and tomahawk chop. On the other side, someone threw a snowball that bounced and hit Braves first-base coach Terry Pendleton.