The phrase "postseason appearance" refers to an event where a sports team qualifies to play in a series of games or matches after the regular season is over. Full definition
It was his first postseason appearance ever, and he walked only one batter to break up a potential perfect game. (sbnation.com)
As the Amazin's tune up fortheir first postseason appearance since 2000, they'll host Dog Day at Shea, which will feature a pregame pooch parade and Stupid Pet Trick auditions. (si.com)
Collins brought the Mets to the World Series and two straight postseason appearances in 2015 and 2016, but his current contract is expiring after this season. (sbnation.com)