MILWAUKEE -- In the aftermath of one of the tougher losses of the season for the Cubs, veteran reliever Michael Fulmer cut to the chase. He made clear what the fan base is feeling and what the front office is weighing while balancing the division race against the looming Trade Deadline.

“I hate to say it,” Fulmer said after the Cubs’ 8-6 loss to the Brewers on Monday afternoon, “but I think they’re must-win games. We’re better than what we’ve been playing right now -- everybody in every aspect."

Every game right now carries extra weight for Chicago.

Yes, there are still three months left on the schedule, but these next few weeks are critical in how the club will determine its direction for the Deadline and the second half. This four-game series against the National League Central-leading Brewers, in particular, offered a great opportunity to close the gap in the division race.

Then, the North Siders’ bullpen -- a group that had stabilized in June and started to look like a real strength -- faltered following an inspiring effort from Fulmer. A late collapse erased an early six-run lead and gave Milwaukee a stirring comeback victory that knocked Chicago seven games below .500 (38-45) and seven back of first place.

Cubs manager David Ross was particularly frustrated with the eight walks issued by his pitching staff. A pair of two-out free passes by setup man Julian Merryweather came around to score in the Brewers’ game-tying three-run rally in the seventh inning.

“We’ve got to throw strikes, challenge guys, make them earn it,” Ross said. “We’ve got to be aggressive. That’s what [the Brewers] do. They walk, strike out. Three true outcomes, and not really slugging that much.

“And we gave them a lot of free passes with a six-run lead. That’s unacceptable.”

A key moment in the game arrived in the fourth inning, when Cubs third baseman Nick Madrigal exited after feeling his right hamstring tighten while he chased down a foul ball. Ross was forced to move Christopher Morel from the designated hitter role to fill in at third.

“I was frustrated. I wanted to finish that game,” Madrigal said. “But everything in my head told me, ‘I’ve got to get out of here.’ These are important games. This series is important, and I want to be in there.”

Madrigal’s departure coincided with Ross’ decision to lift starter Drew Smyly after 3 2/3 innings. The Cubs lost the DH, so after entering the game on the mound, Fulmer took an at-bat in the fifth inning. Five years to the day from his last MLB at-bat, he struck out.

It was a fun moment -- the Cubs had a 6-3 lead at the time -- but Fulmer said, “It’s more fun when we win. That’s our only goal right now.”

Fulmer’s willingness to don a helmet and grab a bat saved Ross another move, and the veteran right-hander provided Chicago with 2 1/3 scoreless innings of relief. That gave Fulmer a 0.52 ERA over his past 15 games (one earned run over 17 1/3 innings).

The Cubs’ bullpen posted a 2.50 ERA from June 1 through Sunday, ranking second in the Majors behind the Braves (2.38) in that span. Fulmer has been a big part of that, along with Merryweather, Mark Leiter Jr. and Adbert Alzolay. That foursome played a key part in Chicago rattling off 11 wins in 13 games in mid-June.

So when Fulmer got the Cubs to the seventh inning with a three-run lead on Monday, it looked like the stars were aligned for another tally in the win column.

“Fulmer was great,” said Ross, whose club has now lost seven of eight. “We just couldn’t close it out.”

After Merryweather’s two walks loaded the bases with two outs in the seventh, Brewers manager Craig Counsell summoned Jesse Winker to pinch-hit, and Ross countered with lefty Anthony Kay. Counsell pulled Winker and called upon right-handed batter Jahmai Jones, who sent a first-pitch fastball to deep center for a game-tying three-run double.

Leiter then allowed two runs in the eighth to seal the loss for the Cubs. He had given up two runs total in June. Three runs were charged to the line of Merryweather, who had allowed three runs across his previous 30 appearances, dating back to April 17.

It was an ill-timed spiral in a crucial game for Chicago.

“When we have a lead like that, we’re going to need to be able to hold it,” Fulmer said. “No matter who it is or what day or how you’ve been pitching, we’ve got to figure out a way to get it done. We’re going to be better, for sure.”