ARLINGTON -- The A's lost another one in heartbreaking fashion on Monday. They held the lead until the seventh inning, when Adrian Beltre tied the game with a two-run homer. The Rangers' third baseman ended the game with a walk-off single in the ninth off reliever Tyson Ross. Beltre, who twice turned down the A's when they tried to sign him, has been a major problem for Oakland over the years. With the win the Rangers' magic number to clinch the American League West is five. Starting Pitching ReportDan Straily took the mound in what is without a doubt the biggest start of his career. He had already lost his spot in the rotation once when Brett Anderson came back from the DL, and it looked like he was in jeopardy of losing it again when the A's decided to go with Travis Blackley instead of Straily on Saturday in New York. Straily showed some serious intestinal fortitude early in the game. His defense let him down twice in the first two innings. Cliff Pennington couldn't come up with a ball in the first that was hit right to him, and in the second inning Josh Donaldson was charged with an error after he made a tough throw to first base that Chris Carter couldn't pick out of the dirt. As a result of the error the Rangers had runners on the corners and one out. Straily responded by striking out Mike Napoli. Mitch Moreland came up next and hit a bloop single to left field that Brandon Moss got a late break on. That put the Rangers on the board. The inning would have been over after the Napoli strikeout, but it raged on instead. Ian Kinsler drew a walk to load the bases. Straily buckled down and struck out Elvis Andrus swinging to end the inning in what could have been a game-changing situation. The pitch he threw Andrus was a four-seam fastball. The A's scored a run in the third and Straily responded with a shutdown inning. He struck out Josh Hamilton swinging to start the inning. Hamilton had just returned from missing time with a sinus issue and blurred vision. Four of the five pitches Straily threw were change ups, likely testing out the slugger's eyes. Hamilton proved there is nothing wrong with his vision by clobbering a change up 441 feet for his 43rd homer of the year.In the fourth inning Straily was tested again after yet another defensive miscue. Carter made a two-base error on an ball grounded right at him. With runners on second and third with two outs Straily sat down Kinsler with a perfectly located 90 MPH for a called third strike. Straily's strikeout of Kinsler was his eighth of the night, matching a career-high. Straily pitched very well when the A's needed it most. He lasted six and two-thirds innings, gave up five hits, two runs -- one earned -- and two walks. He left with a two-run lead. At the PlateThe A's struck the first blow on a Josh Donaldson two-run homer to left field that traveled an estimated 416 feet. The "Bringer of Rain" now has eight home runs this season, and seven of them have come in the 38 games since he was re-called up on August 14. Yoenis Cespedes pulled a screaming ball into the left field stands to give the A's a 3-1 lead. It was his 21st of the year. Rangers starting pitcher Derek Holland has allowed 19 homers since July 7, which is the most in Major League Baseball over that span. He was removed from the game after completing the third inning. The A's plated their fourth run in the sixth inning on a Cliff Pennington RBI single to left field. He hit the ball on the screws. Brandon Moss led off the inning with a double and almost scored on a hard-hit ball by Derek Norris but Beltre was able to knock the ball down and prevent it from getting into the outfield. Josh Reddick went 0 for 3 at the plate. One of his at-bats came with Moss in scoring position. He smashed his bat down in anger as he extended his career-worst hitless streak to 0 for 27. He did draw a four-pitch walk though. Bullpen ReportA's manager Bob Melvin lifted Straily with two outs in the seventh inning as Hamilton was due up. He elected to put in Jerry Blevins, who Hamilton is 0 for 5 in his career against. Blevins walked Hamilton and was removed from the game. Pat Neshek got the call next to face Beltre. He hit a two-run game-tying home run. Ryan Cook retired the Rangers in order in the eighth inning. It was a solid outing for the reliever, who was pitching on his third consecutive day. The A's brought in Tyson Ross to pitch the ninth inning. He promptly allowed back-to-back singles. The Rangers bunted the runners over to second and third and that brought up Hamilton, who was intentionally walked to load the bases. Beltre stepped to the plate and delivered the game-winning RBI single. In the FieldThe Rangers seemed to get a swing in momentum when Hamilton hit his 43rd of the year. Beltre followed with a double to right-center field. With Nelson Cruz batting a ball skipped in front of Norris and Beltre got a little greedy and strayed too far from second base. Norris made a perfect throw to Pennington to cut down Beltre as he tried to dive back to the bag. It would prove to be a huge out as Cruz doubled moments later. Instead of scoring a run, the Rangers ended up with a donut in the run column for the inning all thanks to Norris' throw. AttendanceThe Rangers announced an attendance of 43,044, the third largest crowd in Arlington on a Monday this season. Rangers RacetimeA race featuring historical figures of Texas' past was won by a sprinting Sam Houston.Up NextTommy Milone (13-10, 3.86 ERA) takes the mound against Yu Darvish (16-9, 3.90 ERA) on Tuesday.