Jones had three hits and John McDonald added an RBI double for Pittsburgh, which ended rookie Shelby Miller's streak of 14 scoreless innings at home to start the season. The Pirates have won nine of 12 overall, leapfrogging St. Louis for first place.
Locke (3-1) has worked 13 scoreless innings while allowing five hits his last two starts. The Cardinals got just three singles and advanced two runners into scoring position against the 25-year-old left-hander, who earned the fifth spot in the rotation with a strong spring.
Justin Wilson allowed a walk the last two innings to wrap up the Pirates' fifth shutout, tied for the league lead with St. Louis and San Francisco. All of them have been collaborations.
Miller (3-2) struggled to put away hitters and was taken out after 113 pitches and giving up two homers in 5 2-3 innings. He struck out seven, one off his season best, and was charged with three runs after John McDonald greeted Fernando Salas with a bloop RBI double.
Left fielder Matt Holliday took a circuitous route and just missed a diving catch with the ball deflecting off his left wrist, and Brandon Inge scored from first on a close play at the plate for a 3-0 lead.
Martin hit his fourth homer with a 412-foot drive to straightaway center in the second. He doubled off the right-field fence in the fourth for his fourth straight extra-base hit, two of them homers, then added a two-run shot to cap a five-run ninth.
It was the seventh career multi-homer game and first since June 10-12, 2012, for the Yankees against the Mets for Martin, who's hitting .409 since April 15.
Tabata lined a 2-2 pitch over the right-field wall in the fifth for his first homer, giving him a hit in 21 of 23 career games at Busch Stadium.
Jones' second homer and first in 50 at-bats since April 8 barely cleared Shane Robinson's leaping attempt the wall in the seventh to make it 4-0. First base umpire Laz Diaz initially ruled no homer, but it was quickly overturned after the Pirates appealed.
Mitchell Boggs allowed two hits and a run-scoring groundout by Gaby Sanchez in the ninth. Boggs lost the closer's job earlier this month and has an 11.81 ERA, allowing 14 earned runs in 10 2-3 innings.
NOTES: Adam Wainwright (4-1, 1.93) goes for his fifth win in as many starts in the opener of a three-game series against the Reds and Mat Latos (1-0, 2.16). ... The Pirates are 4-0 in starts by Wandy Rodriguez (2-0, 1.66) entering a three-game series at Milwaukee and Yovani Gallardo (2-1, 4.97). ... Jason Grilli is the first Pirates pitcher to earn 10 saves in April since Mike Williams also had 10 in 2002.
Link to box score: Pittsburgh 9, St. Louis 0
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