The Colorado Rapids have loaned outside defender Dennis Castillo to the USL side the Charlotte Independence, the team announced on Monday. The Costa Rica native made four appearances, including one start and contributed one assist in what was his rookie season last year.

The Rapids made the move because of their depth at outside back. They currently have solid starter Marc Burch as well as Eric Miller and Mekeil Williams. Miller played 26 games and started 23 in 2016, while Williams played in 21 and started 17.

Miller began the season opposite Marc Burch at the right back position this year, but was benched in favor of Williams for the team’s third game against Minnesota United FC after Williams was responsible for the own goal that caused the Rapids to lose 1-0 to the New York Red Bulls on March 11. Castillo hasn’t seen any game action for the Rapids this year.

The recent signing of defender Mike da Fonte likely catalyzed the move to send Castillo to the Independence. 2016 MLS Defender of the Year nominee Axel Sjöberg was lost for six to eight weeks on March 11 due to a left hamstring injury suffered against the Red Bulls, so the team needed to sign a backup to the center backs in case of another injury, a booking or fatigue.

In their press release, the Rapids said that the regular playing time with the Independence will help Castillo further his career. He’ll be eligible to be recalled by the Rapids at any point this year. The Rapids’ next game isn’t until April 9 when they travel to Kansas City to take on Sporting KC.