PHOENIX -- Closer No. 1 has been out since mid-July.

Closer No. 2, since Thursday.

The loss of Brandon Morrow and Pedro Strop has not left the Cubs anything close to out of late-inning options, however.

"It would be real nice if we could be one of those teams that has the best bullpen ERA in the league," president Theo Epstein said dryly before Monday's game.

"Oh, wait. That's us."

You could look it up.

The Cubs led the NL in bullpen ERA by a quarter of a run before their 5-1 victory over to Arizona on Monday, recently taking over the league lead in that category from the suddenly fragile Diamondbacks' corps.

The Cubs did not need a closer Monday, when Javier Baez and Kris Bryant hit two-run homers and Kyle Hendricks was one out short of his fourth career complete game while dropping his ERA to 1.76 in 13 September starts the last three seasons.

"It started with fastball command," Hendricks said. "Willy (catcher Willson Contreras) and I were really aggressive early, which is what I've been needing to do lately."

Cubs left-hander Mike Montgomery (4-5) is scheduled to face Matt Andriese (3-4), who will make his first start for the Diamondbacks after being acquired from Tampa Bay at the trade deadline.

Maybe nothing illustrates the Cubs' all-arms-on-deck bullpen depth more than their 3-2 victory against Cincinnati last Friday, when former Diamondback left-hander Jorge De La Rosa pitched the ninth for his first career save after back-to-back scoreless innings by Dillon Maples and Jaime Garcia.

The Cubs acquired De La Rosa after he was designated for assignment in early August and added Garcia after he had been released by Toronto. Maples has spent most of the year in the minors.

"It says a lot about the mettle of those guys," Epstein said.

"We've had a deep group all year with contributions from many, many relievers -- some expected, some unexpected. They have been resilient. They've been executing pitches. It has been next man up. That's the way it will continue to be.

"Obviously we've missed Brandon and we're missing 'Stropy' right now. Our pen is more than just one or two guys."

Morrow had 22 saves before going on the disabled list in mid-July, and he is expected back soon, perhaps later in the Arizona series. Strop has 13 saves, and five others have at least one.

The Cubs' last five victories have been saved by five different closers -- Jesse Chavez, Strop, Randy Rosario, De La Rosa and Steve Cishek.

"It's not exactly the way we drew it up, but we have quality relievers out there who are unafraid and going right at guys and making quality pitches," Epstein said. "We feel confident we are going to protect leads. It's just a matter of getting those leads."

The Cubs' five-run burst was their biggest since a 6-5 loss to Washington on Sept. 8. They have scored 20 runs in their last eight games.

The Diamondbacks' offense has fared a little better recently, scoring 27 runs on a seven-game road trip to Colorado and Houston and getting only three hits Monday. They have lost eight of 10 to fall five games behind the Dodgers in the NL West and five games behind St. Louis for the second wild card.

"We want to go out and play our best baseball. That's all we can do right now," Arizona manager Torey Lovullo said.

"We've experienced a lot of frustration over the past 2 1/2, three weeks, but we have to place that aside. We haven't played our best baseball in a long time, so we want to focus on being ourselves and see where that lands us."

Montgomery has a 3.87 ERA while splitting time between starting and relieving. He rejoined the Cubs' rotation on Aug. 30 and has been on a limited pitch count since, getting into the fifth inning only once in his last three turn while giving up two runs in four innings in each of his last two.

Montgomery has been much more effective as a starter, going 4-4 with a 3.48 in 16 starts. He has made 19 relief appearances. He did not face the Diamondbacks in their previous series after the All-Star break and has a 1.69 ERA in three career outings against them, one start.

Andriese, who has a 7.31 ERA in six appearances with Arizona, did not have decision in four starts with Tampa Bay this season, where he was used as an "opener," logging only 11 1/3 innings in those starts. He was 3-4 with a 4.07 ERA in 27 appearances with the Rays this season after making 36 starts in 2016-17.

His Diamondbacks ERA was skewed by his last outing, when he gave up seven runs in 1 1/3 innings when he asked to take one for the team in the late stages of a 13-2 loss at Colorado last Monday.

"I think he can go out there and do his job and execute a game plan," Lovullo said. "He's pitched in a very rugged AL East and had a lot of success. Since he's been here, it's been good and bad. Him getting the baseball is going to be a whole new fresh outlook on things. I wanted to see what it looked like."