Colorado right-hander Mason Adams is expected to make his major league debut when the visiting Rockies face the Washington Nationals in the second game of their four-game series Tuesday night.

Adams, the Rockies' 20th-ranked prospect according to MLB.com, was acquired from the Chicago White Sox in a deal for Brenton Doyle at the Aug. 3 trade deadline.

The 26-year-old is 0-0 with a 2.08 ERA in three starts for Triple-A Albuquerque since the trade, leaving him with a 3-4 record, one save and a 3.48 ERA in 17 games (15 starts) for four minor league teams this year.

Mason Adams is set to become the second Adams to join the Colorado roster in as many days. Blake Adams was promoted from Albuquerque on Monday, and he endured a miserable major league debut that night. The 25-year-old right-hander permitted five runs on five hits in one-plus inning.

Mason Adams will face a Nationals team that opened its season-high 10-game homestand by snapping a four-game losing streak with a 13-3 win on Monday.

The change of scenery did nothing for the Rockies, who have lost seven straight games after dropping six in a row at home.

Left-hander Andrew Alvarez (2-5, 3.60 ERA) will start for the Nationals on Tuesday. He lost his past two starts despite allowing just three runs over 10 2/3 innings. Over his past eight starts, he is 0-4 with a 4.19 ERA.

Against the Texas Rangers and Jacob deGrom on Thursday, Alvarez gave up one run over five innings of a 2-0 loss. He yielded four hits and three walks but kept the game close by pitching out of trouble several times.

"You don't want to get into them," Alvarez said of the jams, "but you've just got to keep the composure and trust in the defense. I got a couple key strikeouts, and just to keep the team in it and not give them any momentum."

Daylen Lile led the Washington attack in the series opener. The 23-year-old outfielder had a two-run single, a double and a three-run homer.

"It means a lot," Lile said of his ability to contribute. "It's something we can build off of. Take all the positives we did and take it into (Tuesday) and just try to finish the season strong."

Lile has 16 homers and 71 RBIs in his sophomore season.

Washington second baseman Jorbit Vivas matched his career high with three hits on Monday.

Trailing 2-0, the Nationals struck for five runs in the fifth, aided by two Rockies errors.

"We gotta take care of the baseball better than that," Colorado manager Warren Schaeffer said. "That was an inning that got out of control. This is the big leagues. We need to play better than that."

The Rockies took an early lead on home runs by Willi Castro and Ezequiel Tovar, but Washington scored the next 10 runs. Tovar strained his left wrist diving for a ball in the fifth and left in the sixth.

"(Tovar's) going to be OK," Schaeffer said. "It was the top of the hand. He rolled it up on that diving play. He's going to be all right."

Tovar finished 2-for-2 and is batting .333 (15-for-45) with three doubles, two homers, five walks, eight runs and five RBIs since Aug. 3. Connor Norby had an RBI single and has reached safely in all 12 games since joining the Rockies in a trade with the Miami Marlins.