Junior Lake went 4-for-5 with a home run and three RBI to lead the rebuilding Chicago Cubs past the Arizona Diamondbacks, 4-2, in the first of four games at Chase Field.
Lake's big game came a few hours after Chicago continued to stock its farm system by trading away a proven commodity.
Matt Garza, the Cubs' most consistent starter this season, was dealt to the Texas Rangers Monday for a package that includes infielder Mike Olt, pitchers C.J. Edwards and Justin Grimm, along with a player to be named later.
Chris Rusin (1-0) got called up from Triple-A Iowa to make his second spot- start of the season and was effective over five-plus innings, allowing two runs on two hits and a pair of walks.
Dioner Navarro added a solo homer for the Cubs, who dropped two of three to the Colorado Rockies over the weekend.
Arizona, meanwhile, lost for the fourth time in five games and fell out of first place in the NL West, ending a string of 62 consecutive days atop the division. The Dodgers own a half-game lead after downing the Blue Jays earlier Monday.
Tyler Skaggs (2-2) was dealt the loss after yielding three runs on seven hits over six frames. He did not walk a batter and struck out six.
"He threw decent...made a couple of mistakes," Diamondbacks manager Kirk Gibson said of Skaggs.
Navarro took Skaggs deep to left-center in the second inning, and Lake, in his fourth career game, hit one a little further in the fifth when he reached the second deck for a memorable home run.
"He's done a great job," said Chicago manager Dale Sveum about Lake.
Rusin had singled before Lake's blast and was cruising before putting the first two on in the sixth.
Blake Parker relieved the lefty and gave up a sacrifice fly to Martin Prado and a run-scoring single to Paul Goldschmidt before getting out of the frame with a one-run cushion.
The Diamondbacks, owners of 27 come-from-behind wins on the season, left the bases loaded in the seventh when pinch-hitter Eric Chavez flew out to center field.
After Goldschmidt was stranded on third in the eighth, Lake singled home Darwin Barney for an insurance run in the ninth, and Kevin Gregg shook off a two-out single in the bottom half to pick up his 19th save.
Lake has nine hits in his first 17 at-bats, the most by a Cub since Andy Pafko in 1943 ... Rusin also made a start against the Oakland Athletics on July 2 after the Cubs traded Scott Feldman to the Orioles. He allowed three runs in 3 1/3 innings and did not factor in the decision of an eventual 8-7 loss ... Didi Gregorius had three hits for Arizona ... Skaggs was recalled from Single- A Visalia before the game. The D'backs optioned pitcher Eury De La Rosa to Triple-A Reno to make room on the roster.