SAN DIEGO -- The Cubs held the second National League Wild Card spot to themselves for nearly three weeks. They now have a roommate.

After a 4-0 loss to the Padres on Wednesday night at Petco Park, the Cubs are tied with Milwaukee for the final NL postseason berth. Both teams are 77-68.

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The question now: How will the Cubs respond over their final 17 games?

Their closer, Craig Kimbrel, is out with right elbow inflammation and has no target for his return. Their shortstop, Javier Baez, is out for at least the regular season with a left thumb fracture. They have been shut out three times in the past 11 games.

“We can change momentum, but we have to be more consistent offensively,” manager Joe Maddon said. “We win as a group; we lose as a group. But I do believe to get where we want to go, we have to be a consistent offensive team the rest of the season.”

As recently as Friday morning, the Cubs held a 3 1/2-game edge over their closest Wild Card pursuer. They have lost five of six games in the interim, while the Brewers have gone 6-0 to vault past the D-backs and Phillies and pull even for that second Wild Card.

“They’re definitely playing well, and we’re not,” Maddon said.

The Cubs’ last two losses have come in disheartening fashion. They fell, 9-8, in 10 innings on Tuesday on a walk-off walk. On Wednesday, the game started to slip away when reliever Brad Wieck threw wildly to home plate on a double-steal attempt by the Padres.

Padres right-hander Chris Paddack, in what might be the final start of his rookie season because of an innings limit, kept the Cubs in check for six innings. But the score was only 1-0, via Manuel Margot’s fifth-inning home run off Cole Hamels, when Wieck was called on in the bottom of the sixth.

There were two outs and runners on first and third. Wieck was facing Josh Naylor in a lefty-lefty matchup. Ty France, who was aboard after a leadoff walk by James Norwood, broke from third base, and catcher Willson Contreras came out of his crouch and threw his arms up to alert Wieck. The pitcher stepped off the rubber and had France in no man’s land about halfway down the third-base line. But Wieck’s throw sailed over Contreras’ head, and France trotted home as trail runner Luis Urias took second base.

The Padres tacked on two runs in the seventh on Wil Myers’ two-run single off right-hander Duane Underwood Jr..

“Today, we lost,” said first baseman Anthony Rizzo, who had a leadoff triple in the second inning but was stranded on base. “I don’t care how we win or lose. I don’t care if we make 15 errors, as long as we win. These next two-plus weeks, I don’t care how it’s done, whether it’s pretty or ugly, we just have to win.”

The Cubs ceded the NL Central lead to St. Louis on Aug. 23 and have been in the second Wild Card spot since, with Washington holding the top Wild Card position. The Cubs’ two losses at Petco Park not only opened the way for Milwaukee in the Wild Card chase but also cost them a shot to close ground in the division. The Cardinals lost two straight at Colorado but still hold a four-game edge over the Cubs (and now also the Brewers).

The Cubs play seven of their final 10 games against St. Louis, so a division title remains in play even as the grip on the Wild Card weakens. But there’s a week’s worth of games before then, and the past six days have already shown how quickly things can shift.

“We’ve battled all year,” Hamels said. “As it closes and gets closer and closer, you don’t want to put pressure on yourself or each other. We still need to play our game, do our part and, obviously, battle. It’s 162 games for a reason, and it’s not going to be easy.

“The teams that do win, it’s not necessarily easy for them. But they have the accountability, and they make sure that when the time comes, they get the job done.”