"His homer was just loud," Cards manager Mike Matheny said of Martinez's homer that cleared the lawn beyond the left-field fence. "He's taking great at-bats with us. He's fun to watch."
Astros outfielder Jake Marisnick led off the game with a double and scored on a double-play grounder off the bat of Jose Altuve, who was in the lineup for the first time since March 5 following Team Venezuela's exit from the World Baseball Classic. Marisnick (2-for-3) stroked a two-run double to left in the third and scored on a single by Josh Reddick (3-for-3) to make it 4-0.
A bases-loaded, pinch-hit single by Randal Grichuk in the sixth led to a pair of runs coming home to tie it after the Astros had built a four-run lead through three innings against Cardinals starter Mike Leake.
Leake worked five innings and allowed five hits, four runs and three walks to go with three strikeouts. Astros starter Joe Musgrove, meanwhile, allowed four hits, two runs, one walk and one hit by pitch and struck out two in five innings.
Up next for Cardinals: After their final off-day of the Grapefruit League season on Tuesday, the Cardinals will host the Nationals at 12:05 p.m. CT on Wednesday at Roger Dean Stadium. Listen live on Gameday Audio as Carlos Martinez returns from the World Baseball Classic to make his second Grapefruit League start.
Up next for Astros: Listen live on Gameday Audio as Mike Fiers makes his first start since March 5 when the Astros face the Marlins on Tuesday at 12:05 p.m. CT in Jupiter Fla. Fiers, a candidate for the fifth spot in the rotation, missed a couple of turns following a bout with a sore hamstring.
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Brian McTaggart has covered the Astros since 2004, and for MLB.com since 2009. Follow @brianmctaggart on Twitter and listen to his podcast.
Glenn Sattell is a contributor to MLB.com and covered the Cardinals on Monday.
This story was not subject to the approval of Major League Baseball or its clubs.