The Los Angeles Angels struck first in their battle against the Oakland Athletics but are by no means in the clear in the American League West race. The Angels will try to gain another game in the division when they host the Athletics in the second of a four-game series on Friday. Howie Kendrick provided the walk-off sacrifice fly in the 10th inning of Thursday's 4-3 series opening win, pushing Los Angeles two games ahead in the division.The Angels have won 12 of their last 16 but two of those setbacks came last weekend at Oakland, and the rivals are scheduled to play six more games before the end of the season. The Athletics had to reorder their bullpen this week when closer Sean Doolittle went on the disabled list, and moving Eric O'Flaherty out of a setup role and into the ninth inning has not been the smoothest transition over the last two games. Flaherty allowed a run in a shaky save on Wednesday and was held out for a possible save situation in the late innings Friday as Ryan Cook struggled.TV: 10:05 p.m. ET, CSN California (Oakland), FSN West (Los Angeles)PITCHING MATCHUP: Athletics LHP Jon Lester (13-8, 2.53 ERA) vs. Angels RH Jered Weaver (14-7, 3.72)Lester cruised through seven innings against Los Angeles on Saturday, allowing one run on five hits in seven innings while striking out seven, but did not factor in the decision in a game Oakland ended up winning. The free agent-to-be is 3-1 with a 2.60 ERA in five starts since joining the Athletics. Lester is 2-1 with a 5.24 ERA in four career starts at Angel Stadium.Weaver got a big lead and made it stand up at Oakland on Sunday, scattering three runs and eight hits over 6 2/3 innings to earn the win. The California native had been struggling with his control with 16 walks over his previous five starts but did not issue a free pass to the Athletics. Weaver lost his first two starts against the Athletics in 2014, allowing a total of 10 runs - nine earned - in 11 1/3 innings.WALK-OFFS1. Angels SS Erick Aybar has hit safely in 13 straight games.2. Cook has allowed seven runs in 4 2/3 total innings over his last six appearances.3. Los Angeles OF Josh Hamilton has not homered at home since Aug. 18, 2013.PREDICTION: Athletics 5, Angels 2