Many times over the years a team in the playoffs ends up being the "home team" due to timing or luck and many times that has changed sports history.
10) Super Bowl 14 and 19
Twice a team has played the game (which is determined years in advance) in its own metropolitan area. The LA Rams gave the Steelers a game in #14 and 49ers coach Bill Walsh stated playing #19 at Stanford University Stadium made pregame preparations feel like a home game.
Both times the team with the better regular season won the title including the one loss champ who came closest to a 19-0 season.
9) 2008 AL Central playoff
The White Sox hosted the Twins in a one game playoff for the division title because of a coin flip. What made home field so important was that 17 of the 18 regular season games they played were won by the home team with the Twins winning the one road game.
The winning White Sox playing the game hurt the team in the Division series since it had to use its best pitcher in the playoff game.
8) 1972 AFC Championship game
The Steelers hosted the undefeated Dolphins because that is how the yearly home team rotation worked.
Though the Dolphins won the game, the NFL decided in the off season that record decides home field in playoffs.
7) Super Bowl 48
The NFL decided to play a Super Bowl outdoors in a cold weather city so Met Life Stadium (home of the Jets and Giants) was chosen.
Peyton Manning returned from surgery and was league MVP though he struggled near the end in Denver with the weather.
Seattle is a turf team that prefers bad weather in an outdoor game and it led to the blowout.
6) 1997 MLB playoffs
The rotation of home field advantage in MLB was changed to better record after 4 of the six series to determine the pennants were hosted by the team with fewer wins.
5) The Big 8 champ vs Florida teams in the Orange Bowl
Until the BCS, the Big 8 champ (later Big 12) always played in the Orange Bowl against a team that did not win the SEC, Big 10, PAC 10, or when it existed SWC.
Many of those games that determined the national champion were against Florida State or the University of Miami which played home games in the Orange Bowl Stadium.
Most of the Big 8 teams played home games on a fast artificial turf field while the Orange Bowl surface after grass replaced artificial turf in 1975 was slow.
4) 1954 World Series
Home field flips between NL and AL. I referenced game 1 in a prior post.
That game lead to a Giants sweep over a team that won 114 regular season games.
3) 1984 NLCS
Due to the year the Padres hosted the Cubs and the home team won all 5 games allowing the Padres who won fewer regular season games to win the pennant.
2) 1967 NFL Western Conference Championship
In the first year the NFL had 4 divisions, the Green Bay Packers who finished 9-4-1 hosted the LA Rams who went 11-1-2 because home teams was on a rotational basis.
The Packers winning that game led to the Ice Bowl league championship game the following week.
No doubt the Colts 11-1-2 record is the best record of a non playoff team in league history as it lost a tiebreaker to the Rams to determine the Costal Division champion.
1) 1987 Minnesota Twins
Four AL East teams and four NL teams won more games in 1987 than the 85 the Twins won but due to rotation the Twins had home field advantage in the World Series.
The Twins won every home game while losing all road games to win their first title.