PITTSBURGH -- This two-game series against the Rangers was bound to be a test for the Pirates’ bullpen. Steven Brault and Nick Kingham left their relief roles to start in place of the injured Jameson Taillon and Chris Archer, which meant the bullpen phone at PNC Park would ring early and often.

The Pirates pieced their pitching together for a one-run victory on Tuesday, but it all fell apart in a 9-6 loss to Texas on Wednesday afternoon. Reliever Michael Feliz walked the bases loaded in the eighth inning before serving up a game-tying grand slam to Hunter Pence, and the Rangers put up three more runs against Tyler Lyons in the ninth to deal the Bucs a deflating defeat.

“We weren’t able to close the game out,” manager Clint Hurdle said. “Abner [Doubleday] was on to something when he came up with nine innings. It’s a test, and it tests you differently through different parts of the season, based on what you have available and how the season’s playing out.”

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But how did Pittsburgh go from up four to down three in such a hurry, wasting an incredible home run by Josh Bell and a three-inning offensive outburst? And why did it all happen without any of the Pirates’ top three relievers taking the mound?

Right-hander Keone Kela wasn’t available. In fact, Kela -- who had not pitched since exiting Saturday’s game with shoulder discomfort -- was placed on the 10-day injured list after Wednesday’s game due to right shoulder inflammation. So the Bucs’ eight-man bullpen was down to seven arms.

Setup man Kyle Crick wasn’t available for the series finale, either. The Pirates were off on Monday, but they have a series of restrictions in place to keep their relievers healthy. Crick had pitched three of the previous four days, throwing 43 pitches over that time, so he was unavailable. And so the bullpen was down to six relievers.

Closer Felipe Vazquez also worked three of the previous four days. The Pirates designated him to be available only in a save situation and only for one inning, so their bullpen essentially presented five available arms.

Like Brault, Kingham did everything the Pirates could have asked in his first start of the season. He escaped a 20-minute, 33-pitch first inning without allowing a run and battled through three more. The only blemish was the titanic two-run homer Joey Gallo hit in the third inning. Bell launched a mammoth two-run shot of his own into the Allegheny River in the fourth, so Kingham exited with the game tied.

“He put us in a spot where we were in the game,” Hurdle said. “All in all, he gave us everything he had and left in a good spot.”

Right-hander Richard Rodriguez, the only available pitcher who didn’t work in Tuesday’s game, then pitched two scoreless innings while the Pirates built up a four-run lead. Lefty Francisco Liriano worked a scoreless seventh, putting Pittsburgh six outs away from a two-game sweep.

In came Feliz, who pitched a hitless fifth on Tuesday night. He recorded one quick out, walked Gallo then came a split-second away from getting an inning-ending double play, but Delino DeShields beat shortstop Kevin Newman’s throw to first. Feliz then walked the next two hitters, loading the bases with two outs for pinch-hitter Hunter Pence.

Hurdle’s only other option was right-hander Dovydas Neverauskas, who owns a career 6.28 ERA in the Majors, so he stuck with Feliz. Pence crushed Feliz’s first pitch off the left-field foul pole for a game-tying grand slam.

Feliz walked Logan Forsythe before Hurdle decided he had seen enough. Lyons finished the eighth inning to keep the game tied, but the Rangers pulled ahead in the ninth on Isiah Kiner-Falefa’s RBI double to left, before Rougned Odor hit a two-run blast deep to right.

“We needed to get an out in the eighth inning to get out of that inning,” Hurdle said, “and we weren’t able to close it off.”

Now, the Pirates will embark on their longest road trip of the season -- an 11-game trek through St. Louis, Phoenix and San Diego. The last two days were a test of their injury-depleted roster, and another challenge awaits at Busch Stadium on Thursday night.

“Every game’s a big test. Just because it’s more games, it doesn’t make it more of a difficult trip,” Kingham said. “Just going to go out there, throw ourselves out there and be the team that we are. We’re playing good ball right now. We’ve let a couple slip here and there, but I feel good with where we’re at.”