Complex sentence: He made six appearances (2 starts, 4 sub appearances) in 2005/2006, and paticipated in Middlesbrough's brilliant UEFA Cup run in the 2005/2006 season against Litex Lovech, playing the full game.
Split into simpler sentences: He made six appearances (2 starts, 4 sub appearances) in 2005/2006. He paticipated in Middlesbrough's brilliant UEFA cup run in the 2005/2006 season against Litex Lovech fc as he played the full game.