DENVER -- In dire need of a win at Coors Field, the Colorado Rockies hope starter Kyle Freeland on Tuesday can find a mound groove, heretofore elusive this season.

Eric Lauer will make his major league debut for the San Diego Padres in a matchup of left-handers and former first-round picks. Freeland, a Denver native who turns 25 next month, was the eighth overall pick in the 2014 draft out of the University of Evansville. Laurer, 22, was the 25th overall pick in the 2016 draft out of Kent State.

The Padres pummeled the Rockies 13-5 on Monday night, erupting for nine runs in the seventh when they sent 15 batters to the plate. Those 15 plate appearances tied the Rockies franchise record for the most plate appearances in an inning by an opponent.

The loss was the fourth in five games for the Rockies (12-12), whose home record dropped to 3-7. The Rockies must win the final two games of the series to avoid losing four consecutive home series to start the season.

The Rockies are 1-3 in starts by Freeland, who is 0-3 with a 5.85 ERA and has issued nine walks in 20 innings. He has lasted six innings once this season. Freeland's first start this year was April 3 at San Diego, where he took the loss as he gave up five hits, including two solo homers, and four runs in 5 1/3 innings as the Rockies fell 8-4. He's 0-2, 5.79 in five games (three starts) against the Padres.

Freeland needs to be more efficient and improve the curveball he began throwing this year to give him more speed variance in his arsenal. He has thrown 373 pitches in 20 innings -- an average of 18.6 per inning -- and 60 percent of those pitches have been strikes.

Rockies manager Bud Black said ideally two-thirds of the pitches and Freeland's lack of speed variance has contributed to a high number of foul balls that have elevated Freeland's pitch count.

"He's got to continue to improve on the variance in his velocity from at the high end 93 miles an hour," Black said, "and at the low end, he's throwing this curveball now 78, 79, 80, which is great. But he's got to continue to improve that pitch, because that's the pitch that can create some separation in velocity. As opposed to 93 fastball, 87, 88, 89 cutter-slider and a changeup 86-87. They're all sort of six miles apart, his three best pitches. Everything's hard."

Lauer began the season at Triple-A El Paso, where he went 2-1, 3.00 in three starts and in 18 innings allowed 11 hits and six walks with 19 strikeouts.

"He's got deception and life to his fastball," Padres manager Andy Green said. "There's deception there; just the way arm works causes people not to see it well in most instances. And when he's been successful, that's what you're seeing. You're seeing late reads on the fastball, regardless of the fact that it's not 95 miles an hour.

"He's a low-heartbeat guy that doesn't scare easily that you expect has the right temperament to bring into Coors Field against a very good offense and pitch well. He's a guy that can pitch to hitters' weaknesses and do it well."

In their 10 home games, the Rockies have scored 42 runs and are hitting .245 (81-for-330) with 91 strikeouts. Regardless, Lauer will be on the mound at Coors Field, which can be a harsh pitching environment.

"It's not the type of repertoire that you expect to be impacted much by it," Green said. "He's not going to be heavily reliant on getting sink on his fastball."

He's relying on his location and his command. In that regard, he's probably a little bit more like (Rockies left-hander) Tyler Anderson, who's pitched very well here."

Indeed, Anderson held the visiting Chicago Cubs to two runs in six innings Saturday and was the winning pitcher in Colorado's 5-2 victory. In 22 games (21 starts) at Coors Field, Anderson is 9-5, 3.36.