ST. LOUIS -- President of baseball operations John Mozeliak said Thursday that what the Cardinals do at the July 31 Trade Deadline boils down to one question.

Will the Cardinals improve?

In their 4-2 loss to the D-backs on Friday at Busch Stadium, the first game back after the All-Star break, the Cardinals found improvement in one aspect they were looking for but more of the same in another. The loss put St. Louis one game below .500 and three games behind the first-place Cubs in the National League Central.

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Daniel Ponce de Leon, making an emergency start in place of Adam Wainwright (back spasms), pitched his way to potentially another start. In 6 2/3 innings, the right-hander gave up one run on three hits and struck out seven with no walks. It’s on the heels of Jack Flaherty’s one-run, seven-inning outing against the Giants last Sunday. The Cardinals hoped the starters would build off of Flaherty’s start. Ponce de Leon ran with it.

But the Cardinals' offense couldn't muster more than four hits, continuing a trend the Cardinals have fallen into over the last month and were hoping to break out of in the second half.

“You can’t give in,” Paul Goldschmidt said after facing his old club for the first time since joining the Cardinals. “Keep battling, try to hit the ball hard. I think it’s going to happen, it’s going to turn. You have to try to work, prepare every day, go out there and play hard and try to find a way.

"This game is tough. It will build you up and break you down. As players, you're used to that.”

With no August trades this year, July 31 is the hard deadline for teams to make their in-season moves. That means the next two weeks are crucial to what the Cardinals will do leading up to the Deadline -- buy, sell or hold.

“The assessment is: Can we start playing better?” Mozeliak said. “If we can, then it can be more directionally or specific on what we’ll try to do. But if we’re still hovering around .500, it might be a different course of action.”

The Cardinals could be at .500 and lead the division, with the way the National League Central has gone the past month. But Mozeliak used the record as a proxy, because if the Cardinals are still sitting at .500 at the end of the month, they likely haven’t improved from where they stood at the All-Star break.

“[The first half] certainly could have been worse, but it certainly could have been better,” Mozeliak said. “Things where we showed some hemorrhaging might have been the rotation, clearly from an offensive standpoint, consistency, really coming up with extra-base hits or that crooked number in an inning.”

Ponce de Leon’s start, on top of the season he’s had with the Cardinals in a variety of roles, gives him consideration for another start. If the Cardinals are looking for improvement and consistency in the rotation before the Trade Deadline, it’s hard to look past Ponce de Leon’s 1.99 ERA in four starts (21 2/3 innings) and three relief outings (10 innings).

Manager Mike Shildt said the Cardinals will evaluate in the next few days if Ponce de Leon will start or pitch out of the bullpen Wednesday against the Pirates, which would be his next available day after throwing 105 pitches Friday.

After being moved in and out of the Major Leagues since last year, as long as Ponce de Leon is in St. Louis, he says he doesn’t care what role they put him in. But he also acknowledged he’s done his part to earn another start if needed.

“I always look at it like I want to be the best pitcher,” Ponce de Leon said. “Last year, my goal was to be the best pitcher in Triple-A so the Cardinals had to call me up. This year, it’s any time I get to pitch out there, whether it’s long relief or we’re down 10, or it’s a close game, or I get a start, I want to be the best pitcher. I want to compete with the big names like the Kershaws and Scherzers and Syndergaards. I want to be up there with those guys.”