ST. LOUIS -- Nine days ago, rookie shortstop Aledmys Diaz struck out looking against Astros closer Will Harris as a pinch-hitter in the eighth inning of the All-Star Game. He let the bat sit on his shoulder with the bases loaded, watching a 3-2 pitch cross the plate for strike three.
He wasn't about to let that happen again on Thursday night, when he lined a walk-off single to left field off Carlos Villanueva to give the Cardinals a 6-5 win and a four-game sweep of the Padres.
"I remember the All-Star Game, I had the same chance," Diaz said. "I think today it was just being aggressive. I tried to hit a fly ball and hit a good pitch. [Villanueva] made very good pitches. He hit me with two pretty good sliders, and when I got to 3-2, I just was looking for something up [to try] to put it in play, and he threw me a fastball."
It was Diaz's first walk-off in the Major Leagues. His only other game-ending hit came for his Cuban National Series team, Villa Clara, in a playoff contest
"That one was pretty special for me, too, because it was in the playoffs," he said. "But ... we won four straight games against the Padres, so it puts us in a really good spot right now."
Diaz is in elite company as well. Earlier in the game, he extended his on-base streak to 24 games, the most by a rookie in the Major Leagues and one shy of Jayson Werth and Josh Donaldson for the longest active streak this season.
"I don't think too much on that," he said. "I just keep the same approach."
Diaz almost didn't have the chance to make any approach in the final inning. First base was open, and most other teams would take their chances against Jedd Gyorko instead of Diaz, but not the Padres, who intentionally walked Gyorko to load the bases.
Gyorko hit leadoff on Thursday for the second time in his career because he went into the game batting .619 with six home runs and 10 RBIs against his former team.
"I wasn't real sure what they were going to do," Gyorko said. "Obviously, with having Diaz hitting behind me, it's a tough matchup either way. I just think to get the double-play opportunity, it was probably a smart play."
Diaz's hit secured the Cardinals' longest home winning streak of the season, at four games, and St. Louis has tied its high-water mark of the season at seven games over .500.
"Now he's just taking a nice consistent approach, and I don't think he's getting distracted by streaks or anything else," manager Mike Matheny said. "He's playing the game the right way."
Nick Krueger is a reporter for MLB.com based in St. Louis. This story was not subject to the approval of Major League Baseball or its clubs.