ST. LOUIS -- Baseball can be a cruel game. A hitter can hit the ball as hard as he can, and it will still sometimes land in the glove of an outstretched outfielder or a leaping infielder. A swing can be just off, or the ball can land just outside the fair-ball line.

But that frustration can turn into joy with one swing of the bat, as it did for Paul Goldschmidt on Sunday afternoon when he launched a two-run home run during the Cardinals' 5-2 victory and series win over the D-backs at Busch Stadium.

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Goldschmidt knows the ups and downs. He’s had plenty of each during his nine-year career, and they were exemplified during the first two games of the series against Goldschmidt’s former team. He hit two hard, deep foul balls Friday night but came up emptyhanded. On Saturday, he was robbed of what might have been a home run, but Jarrod Dyson made a leaping grab in center to send Goldschmidt back to the dugout.

He's remained on an even keel through it all. On Sunday, the tables turned for the Cardinals' first baseman when he smashed his 17th home run of the season and his first against the D-backs since he was traded to the Cardinals this past offseason.

“It was a good swing,” Goldschmidt said. “I was able to hit it and get it out of there. The other ones haven't felt bad either. They've been close, but I haven't been able to get the results. Try to keep having good at-bats, hit the ball hard, try to help us win.”

Sunday marked Goldschmidt's second career homer against Arizona's Zack Greinke, who had previously held the slugger to a .174 average (4-for-23) with 12 strikeouts. Goldschmidt's other roundtripper against his former teammate came Oct. 2, 2011, in Game 2 of the National League Division Series, when he played for the D-backs and Greinke was with the Brewers.

Goldschmidt also singled in the first inning Sunday to finish 2-for-4.

Sunday’s results were more hard evidence for what Goldschmidt and St. Louis manager Mike Shildt have seen over the past three weeks as the former works his way out of a slump that gave him the worst first half of his career.

Goldschmidt has raised his slugging percentage from .404 to .428 since the beginning of July with three home runs. Shildt said Saturday that Goldschmidt was in as good of a place offensively as he was during the beginning of the season, when he had nine home runs in March and April combined.

As the Cardinals begin to see more production out of Goldschmidt, it’s important to note what the six-time All-Star has brought to the team outside of offense. Two examples from this weekend punctuate that:

• In the seventh inning Saturday, Goldschmidt made a diving stop at first to save a run and contribute to the Cardinals' eventual 4-2 win.

• On Tyler O’Neill’s double down the left-field line in the first inning Sunday, Goldschmidt went from first to home perfectly, hitting the corner of each bag and running inside the third-base line so cutoff man Nick Ahmed had to throw around him instead of firing it home quickly for a closer play or an out.

“His baseball IQ is very, very high. He’s a student of the game, and he does what a lot of people do that lead,” Shildt said. “He makes people around him better. He doesn’t have to do it vocally. Those baseball things that we value so highly in this organization and community, he’s the poster child for them.”

But Goldschmidt being the complete player he is known to be is what the Cardinals need as they fight to stay in the National League Central race -- their best hitters becoming the best version of themselves.

“Results were better, to get a home run and another hit, but me, individually, I have to do it the whole rest of the second half,” Goldschmidt said. “You can't just do it one game. I think that's the key for us as a team, to show up and do it every day. We've played good for a day or a series, but to win the division or get in the playoffs as a wild card, we're going to have to do it basically every game through the end of the year.”

Goldschmidt knows much of the onus falls on him to produce in an offense that has been stagnant since the beginning of June.

“It's not like it's added pressure, it's just the truth,” he said. “It will take a team effort, but every individual that plays better, it helps the team. I'm trying to do everything in my power to play my best and help us win.”