ST. LOUIS (AP) -- Pitching has not been the problem with the Chicago Cubs. It's the bats that have gone cold.
The Cubs were hitless in 10 at-bats with runners in scoring position and got swept by the St. Louis Cardinals on Sunday night, losing 4-1 for their season-worst fifth loss in a row.
"They kept our offense in check, which they've done to a lot of different teams," manager Joe Maddon said. "We have to get back our offensive mojo."
The Cubs were outscored 15-4 and were 2 for 27 with runners in scoring position in the series overall. They're just 12-32 the last four seasons in St. Louis.
Maddon said the approach has been fine, but noted, "You're not going to be perfect all year." He also added the Cubs have run into some tough staffs.
They've totaled six runs during the slump.
"We've seen Dodger pitching, we've seen Cardinal pitching - that's really good pitching," Maddon said. "And you have a young, inexperienced group offensively, and they're being schooled right now a little bit.
"Eventually, it's going to come back to us and we'll benefit from it."
Carlos Martinez was stingy before and after a lengthy rain delay, and the Cardinals hit a season-high six doubles to extend their winning streak to six games.
Jason Heyward, Yadier Molina and Matt Carpenter each hit run-scoring doubles for St. Louis, which is a major league-best 51-24 with a nine-game cushion in the NL Central. The Cardinals' 29-7 home record also is tops in the majors and is the second-best start in franchise history, trailing only a 31-4 start by the 1885 Browns, according to STATS.
Their home start is the best in the divisional era since 1969, topping the Expos' 28-7 record in 1979.
Before the losing streak, the Cubs had won four in a row. Maddon said players have been "honestly fine" dealing with adversity.
"This group, they're all self-motivated, self-starters, so I have no problem with anything," the manager said. "You can see the inexperience showed up these last seven games, you could see some of it, so that's cool.
"We'll be back."
Martinez (9-3) allowed one run and two hits in six innings with six strikeouts. The 23-year-old right-hander worked two scoreless innings before a rain delay of 1 hour and 43 minutes, stumbled a bit in the third when Dexter Fowler doubled and eventually scored on Anthony Rizzo's sacrifice fly, but allowed only a walk after that.
Martinez and Michael Wacha (10-3) are the first teammates 23 or younger with nine or more wins in the first 75 games since Dwight Gooden and Sid Fernandez had 10 apiece for the Mets in 1986.
Jason Hammel (5-3) struck out seven, but struggled after the rain delay, giving up four runs and six hits in four innings. Hammel worked 7 2/3 scoreless innings against the Dodgers his last time out.
The right-hander said he felt fine after the break but had location woes.
"Missing with teams like this, they are gap-to-gap guys that put good swings on the bat," Hammel said. "It's harder to beat a team when you've got guys just trading places at second base all night long."
Trevor Rosenthal earned his 23rd save in 24 chances in a game that was also delayed 46 minutes before the first pitch.
Heyward made an outstanding sliding catch in foul territory down the right-field line on Kris Bryant's pop-up in the first.
Cubs: LHP Tsuyoshi Wada (deltoid) was placed on the 15-day disabled list and RHP Neil Ramirez (shoulder) was activated.
Cardinals: LHP Jaime Garcia is likely to make his next start Thursday against the White Sox, getting two extra days to recover from a groin cramp sustained running the bases. OF Matt Holliday could begin running early this week.
The Cardinals are 5-0 on Sunday night.
Cubs: Kyle Hendricks (2-4, 4.46) faces the Mets on Tuesday in New York. He has worked five innings each of his last four starts.
Cardinals: Lance Lynn (5-4, 2.84), who faces the White Sox on Tuesday, worked six scoreless innings his first outing off the disabled list from a forearm strain.