PHOENIX -- During the Rockies' final homestand, catcher Dom Nuñez was beaming over the fact that his season -- light on the stat sheet, but heavy on the education -- would last just a little longer.

Nuñez’s offensive struggles and the emergence of Elias Díaz limited his playing time to the point that he is fresh enough to commit to playing 20-25 games as catcher and designated hitter for the Indios de Mayagüez in the Puerto Rican Winter League. But before that on Friday night, Nuñez helped the Rockies.

Nuñez entered as substitute and threw out Jake McCarthy on a steal attempt to end the D-backs’ sixth-inning threat, then delivered a tying solo homer in the ninth to set up a "Story-book" finish. Trevor Story delivered the go-ahead run on a single in the three-run ninth inning as the Rockies took an odd, 9-7 victory at Chase Field to open the final three-game series of the season.

“It’s a high energy clubhouse right now late in the year,” Nuñez said. “That just shows the type of team that we have -- we’ve got a no-quit mentality and we're gonna fight until the end. That's pretty much what you’ve seen, and, hopefully, we can just take this momentum into next year.”

Starting pitcher Jon Gray gave up seven runs in the third inning for a 7-0 deficit. But Sam Hilliard homered during a six-run sixth inning, and relievers Yency Almonte, Jordan Sheffield, Tyler Kinley, Lucas Gilbreath and Carlos Estévez held the D-backs to two combined hits through the game's final five frames.

The Rockies earned their first victory after falling behind by seven or more runs since Aug. 25, 2010, when they erased a nine-run deficit against the Braves to win, 12-10.

It’s unusual for a rookie catcher to be carried on a Major League roster and receive so little playing time. It actually wasn’t planned. Nuñez had a solid Spring Training and the plan was for a more equitable division with Díaz. But with no veteran available, and with the Rockies headed for fourth place in the National League West, there was no need to get one. Instead, Nuñez learned as he played and worked on days he sat.

“At the end of the day, I’m in the big leagues, playing the game that I love,” Nuñez added. “I have to keep a good head on my shoulders. I have to have that perspective of helping the team win.”

The homer, left-on-left off D-backs reliever Caleb Smith, was a culmination of much of that learning. A dead-pull hitter throughout his Minor League career, Nuñez had been trying to diversify his swing. But deep in a batting average hole -- .186 after Friday -- he decided to be himself.

Nuñez fouled off a pair of two-strike pitches to work the count full, then pulled Smith’s fastball over the right-field wall.

“I was trying to do a little bit of everything,” Nuñez said. “Looking back at it, I wish I would have stuck to my guns. But as [hitting coach] Dave Magadan said, 'You don’t really know it until you go through it.'”

Nuñez turns 27 on Jan. 17, but he entered this season with just 16 Major League games played in 2019. He didn’t appear during the pandemic-shortened 2020, but the Rockies kept him on the taxi squad and as their bullpen catcher in order to keep him around veterans and help shorten his learning curve.

There is finishing to do. It’s why the Rockies are sending Nuñez to Puerto Rico. Contributions like those on Friday give Rockies cause to believe that the work is paying off.

“We're super happy [with] Dom,” Rockies manager Bud Black said. “It was a big out with the stolen-base attempt for sure. On the defensive side, calling a good game, pitch selection, receiving [and] blocking. I have no problems. It’s been a little rocky with the bat after April. But that at-bat in the ninth against Smith was a really good at-bat.”