“Make my decision tough.”

That was manager Dave Martinez’s advice to Erick Fedde before Sunday’s 3-0 win over the D-backs as Stephen Strasburg progresses toward his return from the injured list.

Fedde has stepped into the Nationals’ shorthanded starting rotation, like he did last year. Sunday at Chase Field in Phoenix marked his eighth start of the season. That same afternoon, Strasburg (right shoulder inflammation) made a rehab start with the Triple-A Rochester Red Wings.

The Nationals still have to evaluate when Strasburg will be activated, but when he is, they will have to decide whether they go with Fedde in a six-man rotation or move him back to the bullpen. Delivering seven scoreless innings is one way for Fedde to make that decision tough.

“I think that’s probably the best I’ve seen him throw,” Martinez said.

Fedde fanned four and allowed three hits and a pair of walks over an efficient 97 pitches, including 12 ground-ball outs. This performance exemplified his improvement. After giving up six runs in 1 2/3 frames in his first start this season, his ERA over his last seven starts stands at 3.35.

“Any time you can go seven innings scoreless, I’d say it’s a pretty good day,” said Fedde, a Las Vegas native, who dominated in front of friends and family in the stands in Phoenix. “I think I got even stronger as the day went on.”

Martinez lauded Fedde’s command, how he kept the ball down and attacked the strike zone with a mix of his pitches -- 47 sinkers, 20 changeups, 20 cutters and 10 curveballs. It kept the D-backs off balance, too.

“I think it was the cutter-changeup combination, and he was pitching up in the zone,” said D-backs manager Torey Lovullo. “I don't know if that was by design, but I think there were some high strikes and high misses in that upper level of the strike zone that was causing some problems. He was throwing a sinker off the cutter, and he was playing the 'X' game -- he was crisscrossing each side of the strike zone when he could and even at the top of the box.”

On the east coast, Strasburg, who has been sidelined since mid-April, tossed 75 pitches (41 strikes) across 4 1/3 shutout frames for the Red Wings. He struck out six and gave up two hits and two walks. Martinez said Strasburg’s shoulder felt good, and the team will reassess after seeing how he feels on Monday. The Nationals’ options include another Triple-A start or a sim game back with the team.

“I see Stras in the clubhouse all the time -- I know he’s getting close,” Fedde said. “I’ve been in this spot so often, it’s almost something I don’t think about anymore just because I’ve learned the more you think about it, it still doesn’t matter at all. My job is to go out there and pitch well, and today I hope I added something to my resume on why I should still be in the rotation.”

When determining his next steps, Martinez will take the Nats’ schedule into consideration. He would like Max Scherzer to stay on his every-five-game rotation, but there is a possibility other starters, like Patrick Corbin or Jon Lester, might need a day. The team also is cognizant of the fact that Strasburg has been limited and Joe Ross did not play last season. Whatever the Nationals decide, Martinez would prefer it to be a consistent role to avoid injury.

“Either way, he knows how important he is to us, whether he starts again or whether he goes in the bullpen,” Martinez said. “But I really like what he’s done, I really do. He’s pitched well. We have some decisions to make.”