As good as the Yankees have been since the All-Star break (they’re 40-20 -- the best second half they’ve had in the Joe Torre era), the Sox -- still 5 1/2 up on the Bombers -- have not blinked. They have lost 4 1/2 games off their lead since the Midsummer Classic, but after playing at a .609 pace before the break (53-34), they have played .600 ball since (36-24). They have stayed the course. What follows are nine things to watch for this weekend at Fenway. (By Gordon Edes, Globe Staff)