LOS ANGELES -- Jon Lester walked around the mound and Cubs manager Joe Maddon made his way up the steps up that lead from the visitors' dugout to the field at Dodger Stadium. The veteran pitcher had just taken a sharp comebacker off the side of his left foot in the fourth inning, but it was soon clear that he was staying put.

Lester was not going to let David Freese's fluke infield single knock him out of Thursday's game. That hit did, however, ignite a furious offensive push for the Dodgers, who dealt the Cubs a 7-3 defeat in the opener of this four-game series. Lester allowed three home runs in the loss -- Chicago's third through four games on this road trip -- continuing an unfortunate trend for the left-hander.

• Box score

Lester was adamant that the comebacker had nothing to do with the loss.

"It's sore now. It hurt at the time, but it is what it is," Lester said. "It didn't affect the way I threw the ball after that."

Maddon, whose Cubs slipped to 1-3 on the current road trip and dropped one game back of the first-place Brewers in the National League Central, was watching Lester closely after the pitcher took the low liner off the foot. The manager did not see a change in Lester's delivery. There was no decrease in pitch velocity. Lester looked -- as he insisted later -- unaffected by the play.

The box score tells a different story, though.

Prior to Freese's infield hit, the Dodgers had gone 1-for-10 against the Cubs' rotation leader. Starting with that hit, Los Angeles went 8-for-12 against Lester over the remainder of his five-inning performance. That included two-run home runs by Cody Bellinger and Max Muncy in the fourth, when the Dodgers churned out five hits in a span of eight pitches. Freese then added a two-run blast of his own off Lester in the fifth.

"He made some mistakes," Dodgers manager Dave Roberts said of Lester. "I think early on he was just on the edges. The cut fastball, we really weren't seeing. Both righties and lefties weren't taking good swings on the cutter. Once we got him the second, third time around, we just felt better and he got more of the white part of the plate and fortunately our approach was the right one."

That approach was to try to take Lester offerings the opposite way.

In the fourth, Lester fired a 1-0 four-seamer elevated and away to Bellinger, who launched it out to left field for his first of two homers on the night. Two batters later, Muncy took a four-seamer middle-away and sent it tailing to left-center. Freese's blast came against a cutter middle-in, but the Dodgers first baseman belted it into the right-field stands to put the Cubs in a 6-3 hole.

"I felt like I had great stuff," Lester said. "I got beat by three opposite-field home runs. I would like to think that pitching to the big part of the field is still beneficial, but I guess it's not. I don't want to take anything away from their hitters -- they've got really good hitters. Bellinger's probably one of the better hitters I've seen, as far as his approach and not chasing and playing the game and doing all that.

“But, like I said, it makes it difficult when you can't pitch to the big side of the field."

The Dodgers' six-run flurry off Lester more than overcame the three runs Chicago managed off Clayton Kershaw, who allowed a pair of homers (leadoff shots to Kyle Schwarber and Kris Bryant in the first and third, respectively) in his six frames.

Maddon echoed Lester's assessment, agreeing that the pitcher looked sharp despite the line score. On one hand, they were not wrong. Lester's average pitch velocity on both his cutter (88.7 mph) and four-seamer (91.1 mph) was up about 1 mph. On the other hand, Lester allowed a 97.6 mph average exit velocity off his four-seamer (up from 89.8 mph on the season) and a 95.4 mph exit velocity off his cutter (up from 88.1 mph on the year).

So, maybe the "stuff" was good, but the Dodgers were making extremely hard contact.

And for Lester, this fell within a rough stretch that has been riddled with home runs. Over his past six outings, Lester has posted a 7.59 ERA and allowed nine homers in 32 innings, one per 16.3 batters faced on average. In the seven starts prior to that time period, the lefty had a 1.16 ERA in 38 2/3 innings with three homers allowed (one per 52.7 batters).

Heading into Thursday's start, Lester had allowed a .333 average and .597 slugging percentage off his four-seamer and cutter combined over his last five appearances, per Statcast. That was a large spike over his first seven games, in which hitters had a .188 average and .321 slugging against those pitches. The slugging against the cutter, specifically, jumped to .649 from .283.

Whether it was pitch location, a sore foot or the Dodgers making an adjustment after a few looks at Lester, the pitcher was in no mood for circling one as an excuse.

"I've got to pitch better," Lester said. "I flat-out have got to pitch better. It's not a matter of balls or ballparks or whatever. I just flat-out have got to be better."