Richards (1-0) was making his first start of the season -- and just the fourth of his career -- after being recalled from Triple-A Salt Lake on May 29 when Jered Weaver landed on the 15-day disabled list with a strained lower back.
"The command was there tonight, especially my two-seam (fastball)," remarked Richards. "It's good to get the first win out of the way. Tonight I trusted my stuff and went after guys."
The 24-year-old righty allowed four hits and two walks while striking out a career-high eight. Mark Trumbo homered twice and knocked in four runs while Torii Hunter added a solo blast for the Angels, who swept the Mariners in a four-game set from May 24-27.
Blake Beavan (3-5) was charged for all six runs on 10 hits over five frames. Michael Saunders clubbed three of Seattle's five hits and belted a home run as the Mariners fell for the second time in three tries.
"He has turned the corner this year," said Seattle manager Eric Wedge about Saunders. "He has put himself in a good position to hit."
The Angels grabbed a 2-0 lead in the second as Trumbo and Hunter launched back-to-back solo shots, but Saunders cut the margin in half with a solo blast of his own to leadoff the top of the third.
LA plated a pair of two-out runs in the third as Maicer Izturis singled, swiped second and came around to score on a single from Albert Pujols.
Kendrys Morales pushed Pujols to third with a single to center before Trumbo's single to right scored Morales and gave the Halos a 4-1 lead.
Pujols clubbed a one-out double in the fifth and Trumbo followed two batters later with his second homer of the game to dead center field to provide the Angels with a 6-1 advantage.
After Richards was lifted to start the eighth, Jason Isringhausen and Jordan Walden each fired a scoreless inning to nail down the victory.
The Mariners have homered in seven straight games for the first time since Aug. 16-27, 2009 when they homered in 11 straight...It was Trumbo's first multi-homer game of his career.
06/06 01:24:34 ET