PITTSBURGH -- Throughout their Summer Camp workouts, Pirates manager Derek Shelton made an effort to learn as much as he could about Major League Baseball’s new extra-innings rule. Shelton talked to his coaching staff and Minor League managers about strategy, tactics and best practices, preparing for the situation but probably not expecting it as early as the fourth game of the season.

Coming up with the right plan is one thing, however. Pulling it off, as the Pirates learned in their 6-5 loss to the Brewers on Monday night, is another.

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“We had the right situation that we wanted,” Shelton said. “We failed to execute.”

After relievers Michael Feliz and Kyle Crick flushed away the four-run lead they held with one out in the ninth at PNC Park, the Pirates got their first taste of what it’s like to start each extra inning with a runner on second base. Right-hander Dovydas Neverauskas kept the Brewers at bay in the 10th, giving Pittsburgh an opportunity to walk off as winners in their home opener.

Shelton sent speedy shortstop/outfielder Cole Tucker to second base as Pittsburgh’s automatic runner with Jarrod Dyson, Adam Frazier and Kevin Newman due up. The Pirates could play for one run, so Dyson attempted to drop a bunt against right-handed reliever David Phelps. But Dyson struck out, fouling off two attempts before taking a called third strike.

Frazier moved Tucker up to third base with a broken-bat grounder to first base. But Newman couldn’t push Tucker the final 90 feet, grounding out to shortstop. The Brewers responded in the top of the 11th inning, as Eric Sogard hit a leadoff double to left that drove in automatic runner Brock Holt.

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They had another chance to tie it in the 11th, with Newman starting the inning on second base. Newman advanced on Josh Bell’s leadoff groundout, but Erik González struck out and Bryan Reynolds -- extending his hitless start to the season -- went down swinging to end the game.

"I think it's probably what we expected,” Shelton said of the extra-inning scenario. “We got in a situation where we just didn't execute.”

That kind of loss would be frustrating at any point in any year. But the feeling is amplified against a division rival in a shortened season when the Pirates know wins won’t come easy. They were two outs from a victory they could have celebrated for many reasons -- their successful tandem start led by Steven Brault, Chad Kuhl’s successful return to the mound, Colin Moran’s first multi-homer game and so on.

Instead, they were dealt their third loss in four games.

“I think now more than ever, it’s just, take it game by game. Try to get on a roll,” Moran said. “That’s a really good team over there. They’re stacked. They’ve got a really good lineup, good pitching. We were right there with ‘em.”

And Shelton, for essentially the first time as Pittsburgh’s manager, had to deal with some strategic second-guessing. Unlike his predecessor, Shelton has chosen not to reveal the availability of specific Pirates relievers before each game. So when Feliz entered the game to start the ninth inning and Crick came on in relief of him, fans wondered, where was Nick Burdi?

On Sunday in St. Louis, Burdi blew away the Cardinals to finish off Shelton’s first managerial victory. He only threw 11 pitches, and the Pirates were playing a night game Monday after a day game Sunday. Even if it wasn’t a save situation, why not give Burdi another shot?

“He was not available,” Shelton said afterward. “I think coming off of the injuries [Tommy John surgery in 2017, neurogenic thoracic outlet syndrome last year] he’s had and what he's done, we're going to be careful in terms of his usage going forward.”

Shelton had patched together the first eight innings well, using tandem starters Brault (for two innings before a one hour, 42-minute rain delay) and Kuhl (for 3 2/3 innings), then bridging the gap to the ninth with right-hander Chris Stratton, lefty Nik Turley and right-hander Richard Rodríguez.

But the Pirates’ bullpen remains a work in progress, and after an abbreviated training camp, not everyone is ready for a full workload.

They are still without closer Keone Kela, who is on the COVID-19-related injured list. They weren’t going to run out JT Brubaker, a starter his entire career, a day after he pitched two innings in St. Louis. They’re likely going to be careful early on with Clay Holmes, too, after his Spring Training foot fracture.

And they still felt comfortable giving the ball to Feliz, who worked a clean eighth inning on Sunday, with a four-run lead.

But Feliz loaded the bases with one out and plunked Keston Hiura to make it a three-run game. Christian Yelich hit a potential double-play grounder to first, but rather than risk a throw, Bell opted for the safe play at first as another run scored. Feliz gave way to Crick, who immediately served up a game-tying double to Ryan Braun. Shelton said he didn’t think about removing Feliz before that.

"He kept getting ahead in counts, and we were just a pitch away a couple times from getting out of it,” Shelton said. “Unfortunately tonight, we didn't execute the putaway pitch when we needed to."