LONDON (AP) — Arsenal benefited from two defensive blunders to rally for a 2-1 win over Lyon in the first leg of the Women’s Champions League semifinals on Sunday, keeping the English club on course to defend its title. Trailing to Jule Brand’s 19th-minute goal for record eight-time champion Lyon, Arsenal was gifted an equalizer in the 59th when Mariona Caldentey’s low free kick into the area was fumbled backward by goalkeeper Christiane Endler and onto the post. Lyon center back Ingrid Engen, stretching to make the clearance, inadvertently turned the ball into her own net. Engen compounded that mistake by misreading a back-pass from teammate Lindsey Heaps in the 83rd minute. Olivia Smith got to the ball ahead of Engen, had a shot saved by Endler, and recovered to convert the rebound. The return match is in Lyon on Saturday. In the other semifinal, Bayern Munich and Barcelona are locked at 1-1 after the first leg in Germany. The final will be in Oslo on May 23. Arsenal is seeking to beat Lyon in …