Acquiring pitcher Robbie Ray was the main reason Dombrowski signed off on the deal, and the 22-year-old will make his major league debut as the surging Tigers host the Houston Astros on Tuesday night.
Fister went 32-20 with a 3.29 ERA in two-plus seasons for the Tigers, helping them to three straight playoff appearances and an AL pennant. In a move to trim payroll and save money for a potential extension for Cy Young Award winner Max Scherzer, Dombrowski dealt Fister for Ray, fellow minor league pitcher Ian Krol and infielder Steve Lombardozzi on Dec. 2.
Though Ray wasn't rated as one of the top 100 pitching prospects at the time of the trade, Dombrowski said he identified the left-hander as one of the few minor league pitchers he'd want to acquire in a deal for Fister, who is scheduled make his Nationals debut Friday after starting the season on the disabled list.
Ray has shown plenty of promise, going 3-2 with a 1.53 ERA for Triple-A Toledo to earn potentially two starts with Detroit (18-9) before Anibal Sanchez is eligible to come off the DL on May 12.
"He's pitched very well for (Toledo) his last few starts," manager Brad Ausmus told the team's official website. "He's been outstanding. We think he's got the stuff to be able to get big-league hitters out, but he's definitely still in the learning process as a pitcher."
The same could be said for Brett Oberholtzer, who will take the mound for the Astros (10-22) in this contest.
After posting a 3.04 ERA through his first four starts, Oberholtzer (0-5, 5.63 ERA) has struggled in each of his last two. The 24-year-old allowed six runs and eight hits in 3 2-3 innings of a 10-1 loss to Oakland on April 24 before again giving up six runs in 4 2-3 of Wednesday's 7-0 loss to Washington.
The left-hander is allowing opponents to hit .305 while the Astros have lost each of his outings, but the offense has provided him with only seven total runs of support.
''When you get predictable to one side of the plate, major league hitters are going to take advantage of that,'' manager Bo Porter said. ''He left some balls up. When you look at the success that he had last year, it was because of the ability to pitch to both sides of the plate. Right now, it's all to one side of the plate.''
Oberholtzer has never faced the Tigers, who have won six straight after Monday's 2-0 victory in the series opener. Rajai Davis had an RBI single in the seventh before Victor Martinez added an insurance run with a homer in the eighth.
Davis is hitting .337 in 22 games this season, and Martinez is batting .400 with two homers and nine RBIs during an eight-game hitting streak.
''You definitely enjoy the winning streaks,'' said Scherzer, who gave up three hits in eight innings Monday. ''You play 162 games. If you don't enjoy these, you're just going to beat yourself up.''
Dexter Fowler, George Springer and Jonathan Villar had the only hits for major league-worst Houston, which has lost five of six. The Astros scored 20 runs and had 33 hits over their previous three games.
''I wanted to make sure that as a team, we don't lose sight of (having a lot of games left),'' Porter said.
The Tigers have won eight of the last nine meetings, holding the Astros to 22 runs in those games.