PHOENIX -- There was a buoyancy to Arizona’s postgame clubhouse Friday night in Phoenix, where the D-backs had just dispatched the Phillies to even the National League Championship Series and ensure, despite their Game 5 loss the next night, that the proceedings would head back to Philadelphia. Players spoke enthusiastically -- aware of the work ahead but pleased, as reliever Kevin Ginkel put it, to have dispatched the “narrative … that we can’t hang with these guys.”

Standing in stark relief to that atmosphere was rookie left-hander Andrew Saalfrank, who had joined the club less than two months prior. In a bullpen game at Chase Field, Saalfrank was the only Arizona pitcher whose outing did not go mostly according to plan, allowing an RBI double in the fifth inning and walking three consecutive batters in the sixth.

“I think everyone but myself did their job,” Saalfrank said. “It’s a learning day. I didn’t really do anything good out there. It’s frustrating, but there is something to gain from it.”

On the other side of Chase Field, Phillies rookie Orion Kerkering bemoaned missed locations during a second consecutive shaky outing -- the product, he said, of perhaps being overconfident, rather than not confident enough.

“[My confidence is] where it needs to be,” Kerkering said. “Just be ready for every moment every single time no matter the situation.”

Saalfrank and Kerkering had entered the NLCS as key members of their respective postseason bullpens -- a pair of rookies who debuted in September, impressed enough to make their inaugural playoff rosters, then contributed key outs over the first two rounds of the tournament. In the NLCS, however, trouble has tailed both pitchers. Saalfrank walked five batters over Games 3 and 4, allowing runs in each contest. Kerkering took a blown save in Game 3 and nearly endured another in Game 4, walking two batters before recovering to record a single out.

Whichever rookie regains his form quicker could provide a crucial boost over the final days of the series.

“I've spent a lot of time with young players -- a lot of time in the Minor Leagues -- so I tend to trust them,” Phillies manager Rob Thomson said earlier this month. “In order for them to get confidence, you've got to use them, and you've got to show confidence in them. And then the talent will come out.”

For much of the past two months, the talents of Saalfrank and Kerkering have been easy to see -- so much so that Thomson and D-backs manager Torey Lovullo have begun using their rookie relievers in increasingly high-leverage situations.

Given the struggles of other relievers, each team now has little choice but to continue doing so. For the D-backs, Saalfrank profiles as the team’s second-best option against left-handed hitters behind only Joe Mantiply, who cannot pitch every time a lefty slugger emerges from the dugout. That’s especially true against a Phillies team featuring Kyle Schwarber, Bryce Harper and Bryson Stott in its top five lineup spots.

For Philadelphia, Kerkering still possesses some of the sharpest stuff of anyone in the bullpen. With Craig Kimbrel fighting his control, the Phillies understand the importance of finding another late-inning option to prove as effective as Jeff Hoffman and José Alvarado. Kerkering has as much of a chance as anyone.

“Just don't overthink it,” was the rookie’s plan to achieve that goal. “Just keep doing what I've been doing all year. Just keep going. Keep throwing strikes. Be confident in myself and just trust it.”

Between Games 4 and 5, Lovullo planned to engage Saalfrank in a bit of a pep talk, urging him to attack the strike zone and not to show outward frustration when things go wrong -- “fight through the moments that don’t go well, and then continue to be aggressive and stay on the attack,” as Lovullo put it. If Saalfrank can do so, his chances of becoming a positive factor in this series -- and potentially beyond -- will increase.

“We’re not going to be perfect every single time,” Ginkel said. “We want to be, but that’s not always going to be the case. He’s pitched in so many big games for us this year, the last month or so when he got called up. He looks so calm out there. He looks like he belongs there. And he’s going to get the ball again.”