I am assuming that by "championships in pro sports", we are referring to the NBA, NFL, NHL and MLB. Since the NFL is the youngster here all of it's teams can be eliminated immediately. In the NBA, Boston has 21 championship appearances winning 17. The Lakers have 31 championship appearances but have only won 15 of those. ( +1 to the winner of the current series). The NHL is dominated by Montreal with 34 championship appearances, winning 24 of those. But the most championship appearances by any pro sports team is 40 by the New York Yankees who have won 27 championships.
Bill Russel with 11 NBA Championships. and one other professional athlete has 11
Henry Richard of the Montreal Canadians is the other one......he has won 11 Stanley Cups.
Id have to say the New York Yankees with 22
Bill Russell - 11
Terry Bradshaw when he was with the Pittsburgh Steelers with 4 championships.
Michael Phelps has won 33 medals in the World Championships for his sport, Swimming.
Michael Phelps Yogi Berra Bill Russell
Athlete who does it for a living.
no, it is the participants own choice whether or not they want to become a professional athlete. Most of the time a professional athlete cannot participate in the olympics.