Sporting Kansas City currently sit atop the Western Conference in MLS with 22 points and a 6-3-4 record, but there has been one big question asked of this Sporting side as they're almost 40% of the way through the MLS season, and that is if this team has the depth outside the first 11 to make a run. Two times this season Peter Vermes has gone with some squad rotation, both times at the end of a three games in eight day stretch, both of those games on turf, and both of them 2-0 losses.

Does Kansas City really differ from the rest of the league though? Is Sporting overplaying their starters right now or are they in line with the rest of the league with the amount of time their starters are playing? I took a look at the number of minutes played by each team's top 11 players in terms of minutes played and found that Sporting is getting by far the most minutes out of their starting 11. Kansas City is getting 93% of all their minutes played this season from their "first 11" the next closest is Atlanta United who is getting 88% of their minutes from their starters. Sporting is the outlier in the league with the average so far this season among the 22 teams being 79.5% of league minutes coming from team's best 11 players.

It's also an outlier for Sporting KC over the last couple years. I went back and pulled KC's numbers through 13 games from 2016 and 2015 and found that KC was actually below what this year's average is. In 2016 KC got 74% of their minutes from their starting 11 while 2015 saw the number even lower with just 70% of league minutes coming from the best 11. Maybe Vermes is just countering the last few years when he has been lower. At the same time, both 2016 and 2015 when KC had more squad rotation, the club suffered through late season slumps that saw them limp into the playoffs and go out early.

This year, given KC's recent history the club is taking a different approach and starting the best 11 longer. The question will be whether KC can continue with their starters playing this many minutes, especially someone like Ike Opara who has a long, long injury history, or the six starters (Tim Melia, Seth Sinovic, Matt Besler, Roger Espinoza, Benny Feilhaber, and Graham Zusi) who are all over the age of 30. Will their legs still be up for it by the end of the season?

The games against Minnesota United and the Vancouver Whitecaps have led to a number of questions about Vermes' choices in squad rotation. Both games have led to half time changes where a player rotated into the starting 11 has been subbed at halftime for a regular first 11 player; Igor Juliao against Minnesota and Tyler Pasher against Vancouver. The point of the rotating the squad is to give players a break from playing, and both times, Zusi and Jimmy Medranda have had to come on in the second half after a poor performance by their replacement. Is the poor performance by the replacements because of a lack of playing time, or because they're not good enough to actually fill in?

In Minnesota, Sporting was coming off a pair of home wins over Salt Lake and New York in the week before, they replaced Zusi with Juliao, Opara with Kevin Ellis, and Medranda with Soony Saad. Two of those three players (Zusi and Medranda) were back on the field before the end of the game in place of their replacements. Of the three, Juliao obviously had the worst game of the three, and his insertion is probably the most contentious when Kansas City had former starting right back Saad Abdul-Salaam available for the game. Juliao had by most accounts a horrid game, having a big hand in both goals that Kansas City allowed in the game before being pulled at half time for Zusi.

Ellis has been a bit of a whipping boy among many Kansas City fans over the past few years as he's consistently found himself on the field when injuries or form of the other center backs have hit. He's had the unenviable task this season of replacing arguably the best defender in the league over the first three months in Opara and unfortunately the Ellis/Matt Besler partnership hasn't been nearly as good as Opara/Besler has. Besler and Opara have allowed five goals over the 11 games that they've played together while Ellis and Besler have allowed four goals in their two games partnered together.

In Minnesota Ellis had some struggles in the first half, but seemed to play better in the second half after having Zusi inserted next to him at right back in place of Juliao. The least contentious of the rotation subs was probably Saad for Medranda as Saad had started a couple games earlier this season when Feilhaber was out with an injury. Saad though didn't have a great performance on the wing, and chasing the game, Vermes inserted Medranda at the hour mark.

One issue that could be argued in that game is the fact that days before with the game against the New York Red Bulls well in hand, Vermes didn't make a single sub until second half stoppage time when he made all three. Sure it won't make a huge difference, but using a sub around the 70th minute and giving someone a break wouldn't be the worst thing in the world would it? Especially when the club has a substantial lead.

In Vancouver, Kansas City came in on the back of an away draw in Orlando and a home win over the Seattle Sounders. This time they replaced Opara with Ellis again, Feilhaber with Soni Mustivar, Medranda with Pasher, and the injured Dom Dwyer with Latif Blessing. Kansas City struggled offensively and Pasher was pulled at half time for Medranda but KC's offense continued to sputter in the second half. Mustivar lasted less than an hour before being pulled in favor of Feilhaber, and Blessing, the hero in his first start for KC against Orlando didn't have the same luck against Kendall Waston and was replaced by Cameron Porter with 21 minutes to go. Ellis again didn't play really badly, but suffered from the fact that he's not Opara, there were other issues with the team in Vancouver than the Kansas City born center back.

One of the issues may simply be the fatigue of the starters that are playing every game. Eight players have played in all 13 games of the season so far for KC, with six of those players starting all 13. Three of those six (Besler, Ilie Sanchez, and Melia) have played every minute, while a fourth, Seth Sinovic has played all but one minute. Sanchez and Roger Espinoza looked completely gassed in the game against the Whitecaps and their play struggled for it.

The current path that Kansas City is on in terms of playing their starters is seemingly not sustainable given some of the players' history with injuries. Opara in 2016 played over 1,000 minutes in a season for only the second time in career, which is now in its eighth season, while Sinovic has been limited to just over 1,400 minutes over the last two seasons due to injuries. The other issue is Sporting's tendency lately to struggle late in the season, looking run down and tired by the time August comes around, and it's been reflected in their end of season runs. In 2015 Sporting ended the league season on a 3-7-2 run and in 2016 a 3-3-4 run.

Vermes is going to have plenty of choices to make in the coming months with World Cup qualifiers and the Gold Cup potentially taking away players, and a congested schedule as MLS teams enter the US Open Cup in June. KC's depth is going to be put further to the test with all these things on the horizon, and so far that depth either hasn't gotten the chance to prove it, or has fallen short of expectations. The success of this team this year very well could come down to the players currently on the bench getting a number of meaningful minutes this summer, if they can't step up more than they have in their limited minutes so far, KC's starters are going to get run into the ground and be in no position to lead a deep playoff run in 2016.