He currently plays for Sestao, wearing the number 14 shirt. He plays primarily as a Defender. His current market value is estimated at 150K €.

His most recent move was a from CD Basconia to Sestao on 2025-07-01.

Throughout the Spanish Segunda División RFEF 2025-2026, Mikel Montero featured in 24 matches, averaging 0.2 tackles, 0 interceptions, and 0.1 clearances per game, while blocking 0 shots per game.