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The player who was on both the 1969 and 1986 World Series roster for the New York Mets was Ed Kranepool. Kranepool made his debut with the Mets in 1962 and was a member of the 1969 "Miracle Mets" team that won the World Series. He remained with the Mets throughout his career and was still on the team in 1986 when they won their second World Series title. Kranepool's longevity with the Mets allowed him to be a part of both championship teams.
League Championship Series Most Valuable Player Award was created in 1977.
Sure. All NBA teams are limited to a 12-man roster for the playoffs, but everyone on the roster, whether he plays in the actual NBA Finals series or not, gets a ring. That includes everyone on the inactive roster, not to mention all the coaches and the executives.
The last World Series championship was 1908. The last National League championship was 1945. The last NL Division championship was 1989.
Because players need rest.
Mike Torrez
The 2007 NCAA Division 2 World Series was won by the University of Tampa. They beat Columbus State in the championship game 7-2.
The South Carolina Gamecocks won the Division I baseball championship in 2010.
The Cardinals play Division 1-AA football (aka FCS - Football Championship Series) in the Southland Conference.
The Detroit Tigers beat the Yankees in the 2006 Division Series 3 games to 1 and then the Tigers beat the A's 4-0 in the League Championship Series.
MLB teams are allowed to adjust their rosters between, but not during, postseason series. So, an injured player would stay on the roster for the rest of the series even if he's unable to play; after that, the team could replace him on the roster before the start of the next series.
The Division Series is best of 5 games, the Championship Series is Best of 7 games, and the World Sries is best of 7 games.