There is no shortage of candidates, though that won't make picking a starter any easier.
One name that will merit strong consideration is Tim Stauffer, who is already a part of the pitching staff, has a background as a starter and would seem the easiest move when you consider it won't require a roster shuffle.
The only hang-up? Stauffer has, in the first week of the season, shown to be so good and so important in his current role of long reliever that the Padres might be tempting fate as well as risking overworking the rest of the bullpen by moving him into the rotation.
If that's indeed the case, the Padres could recall left-hander Wade LeBlanc from Triple-A Portland to make a start.
San Diego manager Bud Black said he won't make a decision on a starting pitcher for Sunday until later in the week, because he -- understandably -- wants to see if the team needs to press Stauffer into more long-relief duty.
Either way, this is a nice position to be in for Stauffer, the former No. 1 pick who had all but fallen off the Padres' radar only to work himself back on it with a stretch of nice starts a year ago and then a strong spring this year.
On Opening Day in Arizona, Stauffer pitched two shutout innings in what would become a 6-3 loss. The next day, with the rested bullpen, the Padres had fresh arms available in a 6-3 victory, as Luke Gregerson, Cesar Ramos, Mike Adams and Heath Bell were able to cover the last three innings.
Then Saturday in Colorado, Stauffer pitched three scoreless innings in a 14-inning game, three important innings because it allowed Black to hang onto Bell to work the bottom of the 14th inning in San Diego's 5-4 win.
"That was huge," Black said. "Stauff pitched great. I really liked his mix of pitches. He did a tremendous job [there], where every pitch is critical.
"He pitched outstanding. I think that he realized the magnitude of each pitch. Every pitch was thrown with a purpose."
Coming out of the bullpen is something different for Stauffer, who before this season had appeared in 142 professional games, all but 20 of them starts.
"I knew that was the situation I would probably be in ... coming in and going multiple innings," Stauffer said. "But it felt like any other game. It will be a work in progress to see how it [arm] feels, but I don't see any restrictions whatsoever as far as being ready the next day."
Black, a former starting pitcher, is mindful of pulling a pitcher between starting and relief pitching. It's something that's not for everyone, he said.
In 1986, Black opened the season in the starting rotation for the Kansas City Royals. But four starts later, and after manager Dick Howser decided closer Dan Quisenberry wasn't faring well against left-handed batters, Black ended up co-closer for a while, saving nine games.
"You have to mentally prepare differently," Black said. "Most relievers have to be ready mentally every night. That's different than if you're a starter. Your days are structured leading up to your next start.
"You've got to get in the right mental frame of mind. There is a different style of pitching as a reliever."
This is why the Padres might choose to keep Stauffer right where he is, on call in case he needs to pitch long, and possibly, keep the bullpen fresh for another night.
"We'll see what it looks like. We won't know until we keep doing this," Black said. "These guys have special arms. They can adapt sometimes. We're hoping that Tim can adapt."