What Would an Eiberson Castellano Trade with the Philadelphia Phillies Look Like?

Rule 5 Draft selection Eiberson Castellano has impressed early this spring training. Showcasing a four-seam fastball hovering around 96-97 MPH with a plus curveball and serviceable changeup, the 23-year-old right-handed hurler has netted a 31.3% strikeout rate and a .167 opponent batting average over just four 2/3 innings pitched. His 7.71 ERA, 6.36 FIP, and modest seven-to-five strikeout-to-walk ratio needn't raise alarm; spring results mostly don't matter. His plus stuff and 4.59 xFIP suggest he is demonstrating flashes of the potential that prompted Twins decision-makers to take a flier on the relatively unknown arm.

Veterans Jhoan Durán, Griffin Jax, Cole Sands, Brock Stewart, Danny Coulombe, and Michael Tonkin are locked into bullpen roles as the season nears. Louis Varland has impressed early in camp while pitching in one-inning bursts, giving the flame-throwing righty (perhaps) the inside track for the seventh spot in the bullpen. That leaves Castellano competing with Justin Topa, Jorge Alcalá, and Kody Funderburk for the eighth and final role in the unit. Topa is already nursing a shoulder injury, which could force the team to shelve him for the start of the season and ease this crunch, but only slightly.

Nevertheless, spring training is still in its infancy. More injuries or significant performance concerns could arise over the next three weeks, making today's speculation moot. For now, though, Castellano being returned to Philadelphia to award Topa, Alcalá, or Funderburk the final bullpen spot is a reasonable outcome. That being the case, Twins decision-makers could attempt to work out a trade with the Phillies front office to avoid losing the promising righty altogether. While post-Rule 5 Draft trades are rare, they aren't entirely unchartered waters; the two clubs could come to a deal before the season begins. So, what could it look like? Let's take a look at the most recent examples.

Clubs immediately trading players selected in the Rule 5 Draft to different organizations is a common occurrence. However, these transactions will be omitted, as they don't accurately represent what would occur between Minnesota and Philadelphia. With this stipulation in place, we must travel back to 2019, where three trades occurred between the drafting team and the prospect's original organization. The first instance involves the Kansas City Royals and Tampa Bay Rays. Kansas City selected pitcher Stephen Woods Jr. with the fourth pick in the 2019 Rule 5 Draft. The Royals were likely to return Woods Jr. to Tampa Bay. However, the two organizations quickly worked out a trade to remove the restrictions on his roster status with Kansas City.

In return, the Royals sent outfield prospect Michael Gigliotti (ranked 13th on MLB Pipeline) to Tampa Bay. Interestingly, Woods Jr. was absent from the MLB Pipeline's Rays' Top 30 prospect list; it's fair to say that Tampa's farm system was much better than the Royals' at the time. Neither player ever appeared in a major-league game. However, this swap sets a precedent for what a player-for-player swap might look like for Minnesota and Philadelphia. Castellano ranks 16th on MLB Pipeline's Twins Top 30 Prospects list. Here are the four prospects positioned closest to Castellano on MLB Pipeline's list:

• 14th - Infield prospect Billy Amick
• 15th- Infield prospect Rayne Doncon
• 17th - Catcher/outfield prospect Ricardo Olivar
• 18th - Outfield prospect Gabriel Gonzalez

Like every top prospect ranking list, MLB Pipeline is flawed. Nevertheless, it accurately represents which players could be involved in a prospect-for-prospect swap. Doncon, Olivar, or Gonzalez are reasonable candidates to be sent back to Philadelphia. Pitching prospects Travis Adams, Christian MacLeod, and Jose Olivares are viable candidates, too, with C.J. Culpepper being the upper echelon of what the organization should be comfortable parting ways with. Nevertheless, a prospect-for-prospect swap is an unlikely outcome, evidenced by the other two post-Rule 5 trades that occurred in 2019.

Later in the 2019 Rule 5 Draft, the Cincinnati Reds poached outfield prospect Mark Payton from the Oakland Athletics. Cincinnati returned Payton to Oakland. Like Kansas City and Tampa, though, the two clubs then struck a deal, sending Payton back to Cincinnati for cash considerations or a player to be named later. It turned out to be the former. Two picks later, the Chicago Cubs grabbed right-handed pitching prospect Trevor Megill from the clutches (or lack thereof) of the San Diego Padres. Chicago returned Megill to San Diego. However, San Diego also sent him back in exchange for cash considerations or a player to be named later. San Diego, too, chose the cash.

Given what occurred in 2019, the Twins could reasonably acquire Castellano for cash considerations or a player to be named later. However, the prospects made available to Philadelphia would undoubtedly possess less present-day value than Castellano. The wrinkle is that the process of returning Castellano to Philadelphia comes with a separate set of risks. He has to clear waivers first, and there might well be other teams who would be more able and willing to carry him after seeing how he's looked this spring—teams without the Twins' exceptional depth in the relief corps. Now that he's been taken in the Rule 5, a trade can't lift the Rule 5 roster restrictions unless every other team passes on having him with those restrictions in place.

Acquiring Castellano from Philadelphia would be a wise decision for Minnesota, as they could continue to develop him as a starting pitching prospect rather than wedging him into the eighth reliever spot for an entire season with the risk of losing him. Castellano had yet to pitch past Double A in the Phillies system. Yet, he was named the organization's Minor League Pitcher of the Year after generating a 3.99 ERA, 3.40 FIP, and a 136-to-29 strikeout-to-walk ratio over 103 2/3 innings pitched between High A and Double A last season. Allowing Castellano to continue to develop as a starter in the minors under the Twins' superb pitching development program would be the ideal outcome, as the young righty could quickly join Marco Raya, Andrew Morris, and Cory Lewis as the organization's most intriguing starting pitching prospects in the high minors. It's just a tough needle to thread.