It was deja vu all over again for the Boston Red Sox bullpen.The Red Sox handed a 4-3 lead and the chance to pick up a huge series-opening win over a Houston Astros team that couldn’t stop shooting itself in the foot, the bullpen once again let things slip away in heartbreaking fashion.This time it was Lucas Sims’ turn to blow the lead, and the new trade deadline acquisition allowed back-to-back singles with two outs in the eighth. That set the stage for the bottom of the ninth, when Yainer Diaz took Kenley Jansen deep for a towering walk-off home run to beat the Red Sox 5-4.It was Boston’s 12th blown save since the All-Star break, and now the Red Sox find themselves 4.5 games back of the Kansas City Royals for the last American League wild-card spot.The Red Sox also squandered one of Tanner Houck’s best starts in over two months, along with perhaps the worst defensive game the Astros have played all season.Jarren Duran led off the game with a first-pitch leadoff home run, and Boston tacked on a second run thanks to an error by Astros third baseman Sean Whitcomb. It wound up being the first of four errors committed by the Astros, the most in a single game by Houston this season.The Red Sox didn’t play a clean game either, and their big error in the bottom of the fourth proved costly. After the first two batters reached on singles, Rafael Devers was able to gun down the lead runner at the plate on a soft grounder by Jeremy Peña. But whatever momentum Boston got on that play was quickly squandered when Victor Caratini tied the game on a play that the Red Sox immediately wished they’d gotten back.Caratini’s single to right was fielded by Tyler O’Neill, whose throw to the plate was well off the line. As a run crossed the plate catcher Danny Jansen tried to catch Caratini off the first base bag, but his throw sailed into right field, allowing Peña to come in to tie the game at 2-2.Houston repaid the favor, however, in the fifth and sixth innings when a couple of routine plays went awry. Yainer Diaz, a catcher who was playing just his 10th MLB game at first base, was pulled off the bag in both instances. The first came with two outs in the fifth and led to ...