It is, yes, a long season. At least a win today would still give the Phillies tiebreaker over Padres. It's also not the end of the world if they aren't the top seed, based on recent history, even if in reality you want the higher-probability path [just like when you platoon a hitter].
Execution is poor but I think urgency is what works against them. They get tight. They make poor decisions. And they're just a bit lacking in talent [hitters and relievers]. The only thing worse than wasting a bunch of two-run outings by great starting pitchers is when one of them blows both a 2-0 and 4-3 lead, and the bullpen and offense can't pick him up.
