CHICAGO -- Christian Bethancourt's steady work handling four San Diego Padres pitchers was impressive enough Wednesday night.

The 24-year-old backup catcher didn't stop there, though.

Bethancourt, playing in his 11th game of the season, also supplied the game's lone run with a towering solo homer to left, giving the Padres a 1-0 victory in a doubleheader nightcap at Wrigley Field and a twin bill sweep of the Chicago Cubs.

"Bethancourt was unbelievable today behind the dish, the best I've seen him block," Padres manager Andy Green said. "He called a great game and obviously hit the ball out of the stadium. Not a bad day for the kid."

Bethancourt said it was his first big league shutout behind the plate.

"I've been close to it like in the ninth inning, (then) two outs and then single, single," he said. "(Starter) Drew (Pomeranz) was outstanding. He was so nice to catch and to work with, and I got a couple of good at-bats, and that makes the day a whole lot better."

Pomeranz (4-3) struck out 10 and allowed just three hits and three walks in six shutout innings. He made the most of Bethancourt's fifth-inning solo shot en route to his second consecutive win.

"Our bullpen did a great, great job today in both games, and that's huge," Pomeranz said. "If I keep going five or six every time and they come in and throw three or four scoreless, that's pretty awesome."

Four Padres pitchers held the Cubs to four hits while collectively striking out 14 and walking five.

San Diego (15-20) also handed the Cubs (25-8) back-to-back losses for the first time this season. The Padres beat the Cubs 7-4 in Wednesday's early game of the split doubleheader.

The last team to go at least 32 games into a season without losing two in a row was the 1929 Philadelphia Athletics, who dropped their 51st and 52nd games after starting 39-11.

"We don't like it, but it's probably inevitable during the course of a baseball season that you may lose two games in a row," Cubs manager Joe Maddon said. "It's unfortunate it happened on the same day, but I have nothing to lament."

Brad Hand, the third Padres pitcher of the night, worked out of a bases-loaded jam with two outs in the eighth, getting an inning-ending strikeout of Jorge Soler.

Closer Fernando Rodney then faced four batters in the ninth and got Ben Zobrist on an infield grounder for the final out to collect his 10th save and second of the day.

Cubs starter John Lackey (4-2) was nearly as effective as Pomeranz in an eight-inning outing before he was pulled for a pinch hitter. Lackey allowed one run on three hits, struck out seven and walked none. He threw 112 pitches, 81 for strikes.

"It was a great game, Johnny was outstanding," Maddon said. "Their pitchers were good, too. They played well and made the plays on defense. Give them credit. They beat us two games and played well."

Wednesday's second game quickly settled into a pitchers' duel.

Pomeranz gave up two first-inning hits before Anthony Rizzo grounded into a double play. After that, Pomeranz allowed just one more hit.

Lackey, meanwhile, retired 14 consecutive batters until he Bethancourt homered with two outs in the fifth.

In Wednesday's first game, Brett Wallace clubbed a go-ahead, three-run homer in the seventh inning in the Padres' 7-4 victory over the Cubs.

Reliever Carlos Villanueva (1-0) worked one inning -- the sixth -- for the win, and Rodney pitched a perfect ninth for his ninth save of the season. Chicago reliever Pedro Strop (1-1) faced five batters and gave up three earned runs in a rocky seventh to take the loss.

NOTES: Alex Dickerson on Tuesday became the first Padres player to hit a pinch grand slam for his first career home run. ... San Diego departs Chicago for the 90-mile trek to Milwaukee for Thursday's opener of a four-game weekend series at Miller Park. RHP James Shields (1-5, 3.60 ERA) goes against Brewers RHP Jimmy Nelson (4-2, 3.74). ... The Cubs and Padres meet again at Petco Park for a three-game series from Aug. 22-24. ... Cubs C Miguel Montero, on the 15-day disabled list with lower back tightness, went 0-for-3 with Triple-A Iowa on Tuesday, his first appearance in a game since April 24. ... The Cubs have Thursday off before opening a three-game weekend series against the Pirates. RHP Jason Hammel (4-0, 1.85) faces LHP Francisco Liriano (3-1, 3.60) on Friday afternoon.