The more major league hitters see Braves rookie Sean Newcomb, the more they hit his pitches hard. Making it worse for Newcomb is the control issues that haunted him in the minor leagues have resurfaced in the big leagues after a brief hiatus.

The Cubs roughed up Newcomb early on the way to a 5-1 victory at SunTrust Park that ended after 1 a.m. Wednesday following a rain-delayed start . The visitors surged ahead when Wilson Contreras followed Javier Baez’s lead-off homer in the third inning with a three-run shot for a 4-1 lead.

The Cubs (48-45) secured the series victory and will go for the three-game sweep on Wednesday afternoon. After this home stand the Braves (45-47) will travel to face NL West powers Los Angeles and Arizona.

Just five Braves made it past first base against Cubs right-hander John Lackey and four relievers. Newcomb managed to make it through 5 1/3 innings while allowing one more earned run.

“He struggled with his command a little bit but still (the lead) didn’t get completely out of range,” Braves manager Brian Snitker said. “I though he gutted up and made some big pitches at times. It could have got way out of hand but he battled his way through and didn’t let it happen. So that’s one (positive) thing I look at.”

Newcomb, 24, is one of the top pitching prospects in baseball. He debuted in the majors on June 10 and was effective over his first four starts with a 1.48 ERA and 21 strikeouts against eight walks over 24 1/3 innings. Newcomb attributed his improved control to a sharper mental focus on the bigger stage.

But lately the better hitters in the big league have solved Newcomb. The Astros pounded him for seven earned runs over 3 1/3 innings on July 4, the Nationals tagged him for four earned runs over four innings just before the Al-Star break and the Cubs continued to pile on the big left-hander.

The Astros and National are the top two scoring teams in the majors. The Cubs have underachieved this season but they’ve won five consecutive games after the All-Star break.

“All you can do is just learn from it and keep moving forward and trusting my stuff,” Newcomb said. ” I know that I can get people out with any of my pitches as long as its set up properly. I think I just need to slow it down and keep doing what I did when I got here.”

The Braves led 1-0 after Nick Markakis homered against Lackey to lead off the bottom of the second inning. Baez answered with his 11th home run of the season on a 94 mph fastball low in the strike zone.

Newcomb struck out pitcher Lackey before his command faltered, especially on off-speed pitches.

Newcomb walked Ben Zobrist on six pitches. The next batter, Kris Bryant, took a curveball in the dirt for ball two, a change-up in the dirt for ball three and a curveball well outside for ball four.

It appeared Newcomb might limit the damage when slugger Anthony Rizzo grounded out. Newcomb missed low on a first-pitch curveball to Contreras before delivering a fastball down the middle that Contreras launched about 400 feet to left-center field.

“I was trying to do a little bit too much with my off-speed and not looking at it pitch-by-pitch and looking too far ahead,” Newcomb said. “Obviously they are a good lineup but I need to go out and attack a pitch at a time and not worry about what just happened and what is about to happen.”

Newcomb was effective over the next two innings but the Cubs hit three consecutive singles in the sixth to load the bases with no outs. Newcomb struck out pinch hitter Jon Jay before giving way to Luke Jackson, who retired the next two batters with Zobrist’s weak ground out scoring a run charged to Newcomb.

The Braves couldn’t respond against Lackey, who was activated from the disabled list before the game.

Lackey held the Braves to one run over five innings before departing after 86 pitches. The Markakis homer and Freddie Freeman’s first-inning double were the only extra-base hits among the eight total surrendered by Lackey.

“He just kept everybody off balance,” Snitker said. “He was moving it around and changing speeds and we just couldn’t get a hold of him.”

The game started after a rain delay of 2 hours, 30 minutes. It was the 13th weather delay for Braves games this season, including the 11th at SunTrust Park. Rain delayed the series opener against the Cubs on Monday by 63 minutes.

Braves games this season have been delayed a total of 19 hours, 16 minutes when including a stoppage in Miami on April 12 because of malfunctioning lights.