PEORIA, Ariz. -- The Padres made a few decisions regarding their wide-open rotation race on Monday morning. They also opened the door for a few other questions to be asked.

Righty prospect Chris Paddack had his start pushed back a day, meaning Robbie Erlin took the ball Monday in Goodyear against Cleveland. Paddack will instead pitch Tuesday in a prospects game on the main field at the Peoria Sports Complex.

Meanwhile, Joey Lucchesi and Eric Lauer threw bullpen sessions Monday, lining them up to pitch later this week -- but not on their scheduled Wednesday throw day.

As for definitive rotation news, right-handers Bryan Mitchell, Jacob Nix and Pedro Avila are no longer options. Mitchell is now strictly a relief candidate, manager Andy Green said. If Mitchell makes the roster, it will be as a long man out of the bullpen. Nix, meanwhile, is expected to miss the start of the season with an elbow ailment, and righty prospect Pedro Avila was optioned to the Minors.

Here's a breakdown of those decisions and what they mean:

Paddack's start day pushed back
What it means: It's still possible Paddack makes some history with an Opening Day start. (He would be just the fifth pitcher to debut in his team's first game and the first since 1943.) But it seems a whole lot less likely now that Paddack isn't on an every-fifth-day progression toward March 28.

Of course, it was probably always unlikely. Paddack is going to have his innings monitored closely this year, and the Padres might gain an advantage in doing so by moving him toward the end of the rotation. He's still a heavy favorite for a starting job.

Lauer and Lucchesi shuffled
What it means: The Padres entered camp without firm plans for their starting five, meaning their pitchers weren't aligned with their projected start days for the first week of the regular season. As a result, Lauer, Lucchesi and Matt Strahm -- all rotation favorites -- fell on the same day. The Padres needed to reshuffle.

It's worth watching where Lauer and Lucchesi land for their next start this week. That decision could be awfully telling for who gets the ball on Opening Day. Lucchesi has been stretched out a bit more than Lauer, and with Paddack's start day having been pushed back, Lucchesi is the clear Opening Day favorite.

Mitchell out of rotation mix
What it means: Mitchell, who entered camp with every opportunity to win a starting job, simply hasn't been very good. He has walked nine over 8 2/3 innings and allowed six earned runs. His transition to the 'pen began Saturday against the Giants, when he entered in the middle of an inning and pitched a shortened outing of 1 2/3 frames. Mitchell is out of options, meaning he would be exposed to waivers if the Padres were to cut him. Thus, it makes sense they'd give him a chance to win a relief job.

"That's what he's in camp competing for," Green said. "He's going to have the opportunity to throw the baseball here in the last week and make an impression."

Avila optioned
What it means: The decision was pretty straightforward. Avila has impressed this spring, but he still has never pitched above Class A Advanced. His Cactus League start Sunday was always likely to be his last.

In the bigger picture, the Avila move leaves 46 players in big league camp. Seven of those players are expected to open the year on the injured list. The 39 players who remain are all legitimate roster contenders (some more so than others). In the battle for places on the Opening Day roster, it's clearly crunch time.