David Stearns is going on five years running the Brewers’ baseball operations, and he said he’s never seen the team so frustrated.

Pirates outfielder Gregory Polanco capped a breakout series by smashing a go-ahead, two-run home run off David Phelps with two outs in the eighth inning and Josh Hader warming up, and the Brewers were swept by the last-place Bucs with a 5-4 loss at PNC Park on Sunday. It dropped the Crew to a season-worst four games under .500.

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The Pirates have won only seven of their first 24 games, and four of those victories are at the Brewers’ expense. Sunday’s defeat saw the Brewers allow a 4-2 lead to slip away, wasting a tying single from slumping catcher Omar Narváez that snapped an 0-for-19 and three RBIs from Justin Smoak, including a tiebreaking, two-run home run in the sixth.

“I don't think we've played to our capabilities,” Stearns said Sunday morning. “We have time to correct that. We have time to improve and to make this a productive season for us. Frankly, I think we have plenty of time to do that. But we do need to play better, and I think everyone in our clubhouse recognizes that.

“There's probably as much frustration in our clubhouse right now as I've experienced during my time in Milwaukee. I think that's individual-level frustration for guys who aren't performing up to their capabilities, and then there's collective frustration when we look at how we've played together as a team. The challenge for us now is to use that frustration in a somewhat productive manner. Frustration on its own probably doesn't serve us particularly well, but if frustration leads to an increased focus, if frustration leads to a reassessment of where we are, that can be productive. And so that's how we have to use it.”

Said Smoak, “Of course everybody is frustrated. You have ups and downs in the game throughout a season. It’s definitely -- in a shortened season, it stands out more when things aren’t going well.”

At the moment, things are definitely not going well for the Brewers, who had a head of steam after winning three of four games from the National League Central-leading Cubs last weekend at Wrigley Field. Milwaukee promptly dropped five of the next six games at the Twins and Pirates, including a Pittsburgh series in which MLB’s last-ranked offense nearly doubled up the Brewers in hits (37-19). Polanco was 3-for-43 on the year before going 5-for-10 with a double and two homers over the weekend, and though Hader was beginning to get loose in the eighth as the right-handed Phelps prepared to face the left-handed Polanco, “it was David’s inning unless something crazy happened,” Brewers manager Craig Counsell said. Phelps missed with what was supposed to be a back-door cutter, and Polando punished the mistake.

“Nothing has been decided; nothing has been determined,” Counsell said of his team’s 11-15 record. “We had a rough weekend. It didn’t go the way we wanted. We didn’t play well enough to win games.”

The Brewers’ urgency to play better was made evident on Saturday, when the team cut loose slumping veteran Brock Holt after 36 plate appearances. It would have never happened in a “normal” season, according to Stearns, but the Brewers decided they couldn’t wait for Holt to heat up while so many other players -- including Narváez (.414 OPS entering Sunday) and Smoak (.619 OPS) -- were running cold.

Sunday’s game began like so many before, with the Brewers going hitless in their first turn through the lineup. When the Pirates took a 2-0 lead into the third inning against Corbin Burnes, the Brewers increased the margin they’ve been outscored in the first two innings this season 37-5, and the opponent had scored first for the 20th time in 26 games.

Naturally, it has prompted focus on hitting coaches Andy Haines and Jacob Cruz, though Stearns made clear his contention that the staff is not to blame.

“I think our hitting coaches are doing just about everything in their power and potentially more to try to get our group going,” Stearns said. “We’ve got some really talented and dedicated coaches that are working around the clock to try to get us to where we want to be.”

Of the Brewers’ anemic early-game hitting, Stearns said, “I think they [the hitters] are ready. I just don’t think we’re performing. I do think there’s a difference there, and if we had the answer as to exactly how to get our group going in those first few innings, we would have implemented it by now.”

It does not get easier. The Brewers host the Reds next in a four-game series that begins against Cincinnati starters Trevor Bauer (0.68 ERA, 14 strikeouts per nine innings), Luis Castillo (12.3 strikeouts per nine innings) and Sonny Gray (12.5 strikeouts per nine innings).

“We were coming off that Chicago series on a high, and ending the road trip this way is tough,” Phelps said. “But the way this season plays out, one good week can do a lot for us. We have to come ready to play and get back to winning some baseball games.”