Dirk Nowitzki is a retired German professional basketball player, widely regarded as one of the greatest power forwards and the greatest European player in NBA history. He played his entire 21-year career with the Dallas Mavericks, leading them to win the NBA Championship in 2011.
This is based on winning 3 head-to-head matchups with other famous people, but also losing 24 head-to-head matchups.
Most recently Dirk Nowitzki lost a matchup to Seth Rogen (#378) voted by someone from United States.