Taijuan Walker pitched seven shutout innings, allowing just one hit while striking out eight, as the Seattle Mariners won their home opener, defeating the Oakland Athletics 5-3 Friday night.Kyle Seager hit a two-run double for the Mariners, who won their third consecutive game. Rookie outfielder Kyle Lewis extended his hitting streak to eight games, with multiple hits in each of the past six.Walker (1-1) made his first home start for the Mariners since Sept. 30, 2016, a 5-1 victory against Oakland. Walker was traded to Arizona after that season before returning to the Mariners as a free agent this year.The only hit Walker allowed was a leadoff double by Ramon Laureano in the fourth inning. The 27-year-old right-hander walked two.Athletics left-hander Sean Manaea (0-2) retired the side in order in each of the first three innings before running into trouble in the fourth.Leadoff hitter J.P. Crawford beat the shift by grounding a 3-2 pitch into left field for a single. An out later, Lewis lined a single to left-center, sending Crawford to third. Seager then lined a double into the right field corner, scoring two runs.With two outs, Austin Nola hit a chopper to third baseman Matt Chapman. Nola beat the low throw, which Matt Olson couldn’t handle at first base, and Seager scored on the throwing error.The Mariners added two more runs in the fifth.Dylan Moore led off with a double to right and moved to third on a one-out single by Crawford. Right-hander J.B. Wendelken relieved Manaea and got Tim Lopes to ground back to the mound. However, Wendelken’s throw to second to start a potential inning-ending double play sailed over the head of shortstop Marcus Semien and into the glove of second baseman Tony Kemp, who was backing up the play. Lopes reached base on a fielder’s choice, with Moore scoring.Lewis lined a single to center to plate Crawford, giving the Mariners a 5-0 lead.Manaea went 4 1/3 innings, allowing five runs (three earned) on six hits. He didn’t walk a batter and struck out four.The A’s finally scored in the eighth on Semien’s two-run triple off right-hander Bryan Shaw and Laureano’s sacrifice fly.Mariners right-hander Taylor Williams pitched a hitless ninth for his second save.