Real Salt Lake may have ruled the occasion at the final whistle against Houston Dynamo, winning 5-2 at the final whistle, but for a 30 minute period to start the second half, things were more than just nervy - they were nearly disastrous.
First-half leads are dangerous because they put the opposition in a position where they're forced to attack immediately after the second half starts. When that side fighting back is also the home side, the chances increase that the away team will experience a dip in play. This remains the case even when - or especially when - the opposition is down a man.
During that 30 minute period to start the second half, Houston took six shots (only one was on target) and pushed deep into Real Salt Lake's half. RSL took only a single shot and had an overall drop in efficiency. Passing decreased, clearances were less successful, and nothing really worked in our favor.
But when Cole Grossman came on in the 75th minute for Joao Plata - a puzzling substitution on its face - play tilted back in RSL's favor. He immediately dropped into the space typically reserved for Kyle Beckerman and generally stayed there, giving Beckerman some important support in the center of the field and slowing play. The match calmed significantly, chances emerged, and RSL scored two goals to finally seal the match.
This further allowed Luke Mulholland to operate more freely, and his goal was a result of that. He played almost entirely on the right side, and given he was gassed by the 60th minute, it put him in a position to choose his moments - not just push himself into oblivion.
Taking Plata out of the match at that point wasn't necessarily intuitive: He had a fantastic first half, providing support on the left-hand side and putting in the corner that Javier Morales finished. He could have been effective in that final period, too - but given he's only come back from injury recently, taking a risk on him when we're going to lose our top goalscorer to international duty seemed beyond a difficult ask. Luke Mulholland, for all his positive play, isn't the same vital cog.