The way Manchester United players celebrated Robin van Persie’s late tying goal on Sunday against Chelsea said plenty about the state of affairs at Old Trafford, but it also said something about the potential for Louis van Gaal’s club. “It’s fantastic that our players are running until the 90th minute to equalize or win,” van Gaal said following the 1-1 draw against the Premier League’s top team. One minute from the final whistle, van Persie thumped home the equalizer as United, playing without Wayne Rooney and Radamel Falcao, earned an important point. Chelsea, which had taken a 1-0 lead on Didier Drogba’s powerful header early in the second half, remains the team to beat in the league while Man United, unbeaten in its last four matches, should battle for a top four finish. Van Gaal has dramatically changed the roster and after experimenting with different formations his players are starting to develop chemistry. Newcomer Angel di Maria wasn’t at his best but the midfielder drew a late foul on Chelsea defender Branislav Ivanovic, which led to the equalizer. Ivanovic was unfairly given a second yellow card for what appeared to be an accidental foul. Ivanovic’s absence was felt immediately when…