The victory gives Boston a 1-0 lead in the best-of-seven series.
Adam Wainwright pitched into trouble in the first inning walking lead-off hitter Jacoby Ellsbury. Usually sure-handed shortstop Pete Kozma didn't do anything to help his pitcher when he dropped a throw at second base from Matt Carpenter that would have resulted in at least one out, if not an inning-ending double play. Instead it loaded the bases for Mike Napoli. Napoli smacked a bases-clearing double to anchor Boston to a 3-0 lead.
Dustin Pedroia drove in the fourth run on a RBI single in the second inning. Then David Ortiz delivered what could be the biggest blow of the series.
With the bases loaded and one out, Ortiz hit a deep fly ball to right. Carlos Beltran made a grand slam saving catch as he ran into the wall. One run scored on the sacrifice fly, but worse for St. Louis, Beltran left the game after the inning. X-rays on the right fielder's ribs were negative, but he is listed as day-to-day.
Ortiz didn't miss when he hit another over the right field wall in the seventh inning for a two-run homer.
Rookie Xander Bogaerts made it a 8-0 lead with a sac fly in the eighth.
Matt Holliday ended the shutout in the top of the ninth with a solo home run, but the damage was already done.
Wainwright lasted five innings giving up five runs -- three earned -- on six hits and a walk.
Holliday led St. Louis at the plate going 2-4. The Cardinals stranded six runners including the bases loaded for David Freese in the fourth, and runners on second and third for Jon Jay in the fifth.
St. Louis will try to even the series on Thursday with rookie pitcher Michael Wacha getting the start against Boston's John Lackey.