COMMERCE CITY, Colo. -- Rookies Gabriel Pec and Joseph Paintsil scored first-half goals, Riqui Puig scored twice during second-half stoppage time, and the Los Angeles Galaxy polished off a first-round sweep of the Colorado Rapids with a 4-1 victory in MLS Cup action on Friday night.

Pec, who had 16 goals during the regular season, scored his first postseason goal just eight minutes into the match when he deflected a clearing attempt by Colorado goalkeeper Zack Steffen into the net.

The Rapids answered with an unassisted goal by Oliver Larraz - his first in his first postseason - to even the score in the 19th minute of the best-of-three series.

The second-seeded Galaxy took a 2-1 lead into halftime when Paintsil took a pass from Maya Yoshida in the third minute of stoppage time and scored his first postseason goal. Yoshida's assist was his first in two career playoff starts.

Puig, who scored twice in the Galaxy's 5-0 victory in the opening match, put the finishing touch on the victory with goals in the first and third minutes of stoppage time. He did not have a goal or an assist in two playoff starts for LA in 2022.

Diego Fagúndez notched his second career assist in his ninth postseason appearance on Puig's first goal. Pec made it two straight postseason matches with an assist with one on his second.

John McCarthy saved three shots in his second playoff start for the Galaxy after posting a clean sheet in his first. His only other postseason start came in 2020 with Inter Miami.

Steffen totaled four saves in his 10th career postseason start and second with the seventh-seeded Rapids.

The Galaxy outscored Colorado 15-4 in four matchups this season. LA improves to 9-2-0 all time against the Rapids in the postseason, including 4-2-0 on the road.

LA will face the winner of the series between No. 3 seed Real Salt Lake and No. 6 seed Minnesota United in the next round.