CHICAGO – June can’t end soon enough for Cubs pitcher Jeff Samardzija.

After a great start to the season, Samardzija has sputtered in his last four starts – all losses – and the Mets became the latest to victimize him. Hoping to sweep the Mets at Wrigley Field for the first time since 2004, the Cubs instead were on the receiving end of their worst loss in nearly two years.

Unlike the Cubs, the Mets took advantage of the hitter-friendly conditions at Wrigley Field and cruised to a 17-1 win behind consecutive six-run innings. Samardzija surrendered nine runs in 4 1⁄3 innings, and reliever Casey Coleman didn’t fare much better in his 12⁄3 innings of work, giving up seven runs. The Mets hit four home runs, including a Scott Hairston grand slam.

It’s the Cubs’ worst defeat since an 18-1 shellacking Aug. 2, 2010, against Milwaukee. Since 1900, the Cubs have lost 26 games by 15 or more runs.

“The walks are unacceptable, especially with the conditions we had today,” Samardzija said. “If you’re gonna give up home runs, they have to be solo home runs. You just can’t put those guys on base for free.”

Manager Dale Sveum couldn’t pinpoint Samardzija’s issues during his rough four-start stretch, but he’s a bit concerned the longer Samardzija struggles. Even if Samardzija is hitting a wall in his first season as a starter, the Cubs aren’t deviating from their plans.

“It could just be confidence; it could be mechanical,” Sveum said. “It could be all of the above. Obviously the magic question is which one it is.”

After getting roughed up, Samardzija (5-7) was adamant nothing is physically wrong with his arm and maintained he’s only experiencing a “speed bump.”

“For me, it’s more mental than physical,” Samardzija said. “My body feels great; that’s not the issue.

“I need to make better adjustments and make better pitch selections.”

Still, it’s alarming that during his four-game skid Samardzija has given up 25 earned runs in 181⁄3 innings and walked 10 batters. Samardzija’s four walked batters all scored in the loss.

“I’m not concerned as a whole, I’m just upset as a competitor and a teammate of my guys who have been playing their butts of here these last few days,” Samardzija said. “To come in here and let them down isn’t what I’m about. It doesn’t sit well with me at all.”

An inability to hit left-handers again doomed the Cubs (26-49) with lefty Jon Niese on the mound for the Mets (40-36). They managed only one run on eight hits off Niese (6-3) in seven innings of work. Oddly the Cubs’ lefties had the most success combining for five hits. The Cubs fell to 4-17 against left-handed starters this season.

“You just got to remind yourself to keep working,” outfielder Joe Mather said. “There’s really nothing else you can do. … You’ve got to keep putting your time in. Bottom line is we’re still out there, it’s our job.”