Howard, a St. Louis native, has hit safely in 22 of 27 regular season games at Busch Stadium. He has 38 RBIs in St. Louis and a .374 batting average.
Howard also has been hot on the road. In his last 15 games away from Philadelphia, he is hitting .350 with three homers and 14 RBIs.
Buchanan (3-3) made his deepest start yet, pitching 7 2-3 innings. He threw 105 pitches and kept the Cardinals off balance and off the scoreboard until the eighth. Buchanan allowed four hits and a walk while striking out four.
Jonathan Papelbon pitched the ninth to pick up 17th save in 19 opportunities.
Shelby Miller (7-6) gave up seven hits and three walks in 6 2-3 innings. Miller has thrown six innings or more in his last four starts.
Howard's homer in the sixth — his 10th career homer at Busch Stadium — came after Utley led off with a single. Howard went to the opposite field and his ball just flew inside the left field foul pole. It was his 14th this season and gave the Phillies a 4-0 lead.
The Phillies have won four of five and are 7-2 in their last nine games. St. Louis has lost its last two after winning five in a row.
The Cardinals had runners at first and third with one out in the second inning but Buchanan pitched out the jam and then again in the sixth when Miller doubled to lead off. Four of Miller's five hits this season have been doubles.
Third baseman Reid Brignac was hurt on a play at first in the fifth. Matt Adams dived to nab the ball behind the base. Adams flipped it to Miller, who slid into the base for the out. Brignac extended his left foot and jammed it into the base. Brignac lay on the ground before being helped off the field with a noticeable limp. The club said Brignac sprained his ankle and will be checked Friday.
NOTES: The Cardinals said P Michael Wacha will miss Sunday's start in the series finale with the Phillies. Wacha has thrown 90 1-3 innings this season. Reliever Carlos Martinez, who started Monday against the New York Mets and threw 59 pitches, will take Wacha's place. ... St. Louis P Joe Kelly, who has been on the disabled list with a hamstring injury since the middle of April, threw a bullpen session before the game. No date has been set for a rehab start. ... Cardinals P Tyler Lyons was activated Thursday from the disabled list and optioned to Triple-A Memphis. Lyons went on the DL on May 13 with a shoulder strain. ... Philadelphia SS Jimmy Rollins and 2B Utley have started 1,130 games together as a double-play combination, the most among all active combos in the leagues. ... Rollins extended his hitting streak to 13 games.
Link to box score: Philiadelphia Phillies (33-38) 4 at St. Louis (39-34) 1
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