Tactical Recap: RSL 1-2 Sporting Kansas City

Down a man, Real Salt Lake lost to Sporting Kansas City in the worst of ways by conceding very late into stoppage time on a set piece — but one might look at the side after Chris Wingert was sent off when looking for an explanation of the movement leading to the loss.
Set pieces
In the inimitable words of Alexi Lalas: Set pieces. One can blame refereeing errors all one likes, but referees don't force defensive errors. Not directly, at least — one might argue that Chris Wingert's presence in the box may have helped, but contemplating that puts us firmly in the realm of fantasy. Simply, the entirety of the team must do better on set pieces. We're surely improved from earlier in the season, but when you're on an at-best second-choice defensive group, it might be a little inevitable. Still, these are fundamentals.
Effects of the sending off
Sporting notably controlled the match from the time Chris Wingert left the match, holding possession advantages from the 70th-75th minute interval forward. It had, until that point, been a relatively back-and-forth affair, with neither team holding significantly more than 25% more possession in a given five-minute interval. Interestingly, RSL actually controlled an advantage in passing until the final 30 minutes of the match, during which Kansas City completed more passes than some terribly mediocre teams have against us this season — 165 of 188 for a staggering 87 percent accuracy. 100 of those successful passes were in the attacking half. When down a man, especially late on, some semblance of continuity could have saved Real Salt Lake at least a point.
(Possession intervals and other interesting stats can be seen on MLS's Golazo! beta: https://golazo.mlssoccer.com/matchcenter/2013-07-20-real-salt-lake-vs-sporting-kansas-city/stats) 
The diamond, down a man
It all comes to a head, then: Jason Kreis was forced to make a defensive substitution, which has been fairly opposite to his intentions throughout the rest of the season. He didn't have many options, and given the danger Sporting KC presented, one might say he made the right decision. But let us ponder for a moment what the match would have been like with two forwards — one playing deeper on the flank as Plata is inclined to — and three defenders. The problem rapidly became that RSL's midfield couldn't win the ball, and with a game plan that depends largely on pressure higher up the pitch, having only a single forward hurt.
When that forward is the ever-wily Olmes Garcia, the problem is magnified: Garcia, for all his magic and ability, is not a forward best-suited for a side down a man and almost entirely on the back foot. But the thought process is positive: Garcia's ability to run at defenders and create havoc is tactically profound, but it does require that he has either a forward partner to close down other options in a high press, or that he has one or two midfield players making runs at defenders as well. Neither was the case once he came on, and as a result, his pressure was largely cursory for the Kansas City back line to deal with.
A 
regular contributor to RealSaltLake.com, Matt Montgomery runs the SB Nation blog RSL Soapbox. Follow Matt on Twitter @TheCrossbarRSL