Ryan McMahon's first-inning grand slam was the first of four homers hit by Colorado on Friday night as the visiting Rockies defeated the San Diego Padres 9-4.

The Padres, however, experienced an even bigger loss when shortstop Fernando Tatis Jr. sustained a partial left shoulder dislocation while sliding into third in the first inning. He immediately left the game.

Tatis has experienced the same issue on three occasions this year, including missing nine games while on the injured list after getting hurt on April 5. After the Friday game, the Padres announced that Tatis is day-to-day.

After McMahon gave the Rockies a 4-0 lead, San Diego native Connor Joe and Brendan Rodgers each hit a two-run homer off Padres starter Ryan Weathers in the fourth. Elias Diaz greeted reliever Nabil Crismatt with a homer leading off the fifth.

Rockies starter Jon Gray (7-6) held the Padres to two runs on four hits and three walks with four strikeouts over 6 1/3 innings to post his second victory against the Padres in a span of 19 days.

The Rockies are a major-league-worst 12-39 on the road this season, but they have won three of their past four games in San Diego over the past three weeks.

The two runs against Gray came on the first of a pair of two-run homers hit by Padres third baseman Manny Machado. Tyler Kinley served up the second. Machado has 20 homers on the season, including four in the past five games.

Weathers (4-3) gave up eight runs on eight hits and three walks with two strikeouts in four innings.

The 21-year-old left-hander retired the first two Rockies he faced in the first before C.J. Cron walked and advanced to third on Charlie Blackmon's ground-rule double. Weathers then walked Diaz ahead of McMahon's 17th homer of the season, a blast into the left field stands.

McMahon drew a walk from Weathers to open the fourth. Joe then hit his second homer of the season to left. Weathers struck out the next two hitters before Raimel Tapia singled in front of Rodgers' eighth homer of the season.

--Field Level Media