By Chris Smith Philadelphia Union head coach Jim Curtin has praised his players for their ability to ‘grind and fight’ their way through the MLS Cup Playoffs. The Union enjoyed another stellar regular season, finishing top of the Eastern Conference and boasting the best offensive and defensive records in the league. Curtin’s side finished level on 67 points with LAFC, but lost the Supporters’ Shield on games won – Major League Soccer’s primary tiebreaker. Philadelphia have enjoyed a strong Playoffs run so far, too, first beating FC Cincinnati 1-0 before coming from behind to see off NYCFC 3-1 …