CHICAGO -- Despite struggling on the mound most of the game, Ian Kennedy executed his pitches when he needed it the most.
On a cool, unseasonably summer night in Chicago, Kennedy (8-9) won his third straight decision. He allowed three runs and three hits, while striking out six and pitching around a season-high five walks in six innings.
With the bases loaded and one out in the fifth, Kennedy struck out Anthony Rizzo and got Starlin Castro to ground out to end the inning.
Rizzo, currently one of the hottest hitters in baseball was coming off a two-homer game against the Padres on Tuesday.
''He's been swinging the bat very good, all season he has. If you make a mistake to him it will cost you quite a bit. I knew I had to execute and bear down in that situation. It was a big at-bat in the whole game and it kind of stopped their momentum,'' Kennedy said.
Medica finished with three hits and drove in two runs for the Padres, who came into the game with baseball's worst batting average at .215.
Luis Valbuena hit a three-run homer for the Cubs, who have lost 12 of 15.
Cubs starter Tsuyoshi Wada (0-1) allowed five runs, five hits and four walks in four-plus innings. It was his second career start after receiving a no-decision against the Reds on July 8.
''On the hill he looks as composed as anybody, but he didn't find his rhythm and command today as he had in his last outing against Cincinnati, but he kept grinding. He did try to get through it,'' Cubs manager Rick Renteria said.
After a leadoff walk in the first inning, Yangervis Solarte hit an RBI triple to right. Solarte scored on Carlos Quentin's sacrifice fly to give the Padres a 2-0 lead.
Solarte was acquired on Tuesday from Yankees, centering around a trade that sent Chase Headley to New York.
''Right off the bat that was great to see. It brought us some energy,'' Padres manager Bud Black said. ''He looked good, everything as advertised. It was good to get him acclimated.''
Jeff Francoeur, who had his contract purchased by the Padres from Triple-A El Paso before the game, singled in his major league season debut, then scored from first on Chris Nelson's double. He finished the game 1 for 3 with a walk a sacrifice fly.
Kennedy was unable to hold the 3-0 lead in the fourth inning. He allowed two walks, then with two outs, Valbuena drove Kennedy's 0-1 pitch into the bleachers in right field to tie the game. It was Valbuena's sixth homer of the season.
''It was just a bad curveball I threw to Valbuena. That was frustrating because I thought my curveball was pretty good all night,'' Kennedy said. ''That was by far the worst one I threw all night.''
Wada, who struggled with his control the entire game, walked the first two batters in the fifth. His night ended when Medica hit an RBI ground-rule double in the ivy in left. Reliever Brian Schlitter continued with the control problems for the Cubs. He walked Rene Rivera with the bases loaded to give the Padres a 5-3 lead.
Pinch-hitter Seth Smith and Medica had RBI singles in the eighth for the Padres and Francoeur added a sacrifice fly.
The Cubs promoted OF prospect Jorge Soler to Triple-A Iowa where he will join infielders Kris Bryant and Javier Baez. ''Our last big call was around the All-Star break. With Soler, we talked about the fact that he really looked like he was on a mission. He came off the DL (hamstring injury) without missing a beat. It was remarkable for him not to show any signs of rust, in fact the opposite. And he said, now is my time,'' Cubs president of baseball operations Theo Epstein said. ... Francoeur took OF Cameron Maybin's spot on the roster. Maybin was suspended 25 games Wednesday for testing positive for amphetamines.