There is certainly a case to be made that when healthy, the Philadelphia Phillies have the best starting rotation in not just the National League, but in all of baseball.

The problem, though, is that key phrase of "when healthy." Ace Zack Wheeler missed time last season, and now, right in the midst of a push for the top NL wild-card spot, the Phillies rotation took a major hit.

Jesus Luzardo is headed to the IL

According to Phillies beat writer Matt Gelb, left-hander Jesus Luzardo is headed to the injured list with left shoulder inflammation. Luzardo was scratched from his start over the weekend against the Atlanta Braves, and things have not progressed like the team had hoped.

The injury comes at an extremely unfortunate time as Luzardo's most recent start of the season was his best one. He tossed a complete game shutout against the Atlanta Braves, helping Philadelphia stay within striking distance in the NL East race. Entering play on Tuesday, the Phillies are 4.5 games behind the Braves. Philadelphia is also in a tight wild-card race. The Phillies are a half-game behind the Chicago Cubs and a full game ahead of the San Diego Padres. The Arizona Diamondbacks are 3.5 games behind the Phillies.

The complete game lowered Luzardo's season ERA to 2.87, the 12th lowest ERA in MLB. It was also the seventh consecutive start that Luzardo allowed two or fewer earned runs.

The timeline for a return is a bit concerning

Luzardo is not eligible to be activated off the injured list until the last day of the regular season. That would mean all things and progressions would have to go perfect to have Luzardo feeling ready to pitch.

Even then, a start on the last day of the season would put Luzardo pitching on short rest in Game 3 of the Phillies NL wild-card series.

Manager Don Mattingly did not rule out a postseason start for Luzardo, but the optics behind it will be tricky to figure out with no opportunities for rehab appearances in the minor leagues.

Who can Philadelphia turn to in place of Jesus Luzardo?

The two easiest options for Philadelphia to replace Luzardo with in the postseason are Aaron Nola or Andrew Painter. Each of those have struggled, though, as Nola has posted a 4.69 ERA this season and Painter has been even worse with a 5.54 ERA.

In a potential Game 3 of a wild-card series game, it would appear that the Phillies would be best suited to use an opener in front of Nola or Painter. Even a full bullpen game that included Nola or Painter or both in the middle could be an option.

Regardless of what the decision is, the downgrade from Luzardo to Nola or Painter cannot be understated, and it will put Philadelphia in quite a predicament if the situation presents itself.