Of all the demons the Dallas Stars have battled during the Glen Gulutzan tenure, perhaps the most frustrating has been the struggles on the back-end of back-to-back games.

It's no secret at this point that that Stars are 1-15-2 under Gulutzan on the second day of a back-to-back set, the most recent loss a 7-4 dispatching by the Calgary Flames on Wednesday.

But what is it about these games that the Stars struggle so mightily with? Travel has been brought up time and time again, but in the pair of home-and-home series they've had during this stretch, they've struggled just as much as they did when the other team was rested. Playing the backup goalie, be that Andrew Raycroft, Cristopher Nilstorp or most often Richard Bachman, is also a part of the problem, but Kari Lehtonen has started six games during that stretch. He hasn't fared much better than his fellow netminders, being yanked twice (once due to injury) with a 1-4-1 record.

So I decided to dig into the stats a little bit to see if I could pinpoint just what is going wrong. Mark Stepneski got me started with his handy chart of front-end and back ends of back-to-backs over the past two years, and I ran the gamesheets to pull out more statistics.

While the results aren't stunningly conclusive, they do point to two areas where the Stars are giving up goals - overall shaky goaltending (likely related to the quality of scoring chances allowed), and a problematic penalty kill.

The most clear one is the penalty kill, so let's start there. Here's a pair of tables, one for last season and one for this one, comparing the Stars special teams play in all games, back-end of back-to-backs and the remaining games in a season.

2011-2012

2013

The power play last year was actually more efficient on the back end of back-to-backs (though given last year's power play, that's not saying much), so I'm less inclined to give a lot of weight to the struggles this year. The more consistent problem is the dramatic dip in the PK percentage.

Despite giving up essentially the same number of penalties to kill in back-ends versus the remaining games (68 from 2011-12 and 10 from this year), the Stars penalty kill gives up about 0.20 goals against per game, and the PK percentage drops by around 7 percent. That's a huge drop, and the fact that the numbers are almost exactly the same this year versus last season makes me inclined to call it a trend.

Why would that be? Your guess is as good as mine, honestly. A good portion of it may be related to the problems with save percentage, which leads me to the next charts.

The other ridiculously dramatic statistical swing in the back-end games comes from raw goals against versus goals for, part of which is directly tied to a drop in save percentage. Here's charts detailing the swings in goals for and against, shots for and against and save percentage. The caveat on save percentage is a team statistic in this chart and therefore includes empty net goals.

2011-2012

2013

The shot differential does have a bit of a swing to it on the back-end of back-to-backs, though this year the Stars are actually allowing fewer shots to the opposition in those games after a slight uptick in that area last year. The Stars are also taking slightly fewer shots.

But that shouldn't account for the wild swings in goals for and goals against. For some reason, the Stars simply can't seem to turn their shots into goals at the same rate in back-end games, while at the other end of the ice the opposition is feasting on a fairly similar amount of opportunities.

Some of that is obviously dependent on the quality of chances these shots represent, and I simply don't have access to those numbers at this point. It would be very interesting to know if the Stars were containing the number of shots overall but giving up significantly more prime scoring opportunities. My suspicion is that's a very significant statistical swing from their other games.

The other stark contrast here is obviously the save percentage, which as I mentioned above spans the four goalies the Stars have had up over the past two seasons. The starts break down as this - four for Raycroft, six for Lehtonen, seven for Bachman and one for Nilstorp. That is an above-average helping of backup goaltending, but not ridiculously so, and honestly, everyone has struggled.

Even when you break out the differences in goals against per period, it's about what you'd expect from teams who are getting beat handily.

2011-2012

2013

I wish I had shots-by-period totals from the season to compare those, but my ability to find such things in the NHL.com database failed. The data I have from just the back-end games is that the Stars are getting outshot by 1.5 on average in the first period, 3 in the second and outshooting their opponents by 1.5 in the third.

As far as brilliant solutions to the problem of back-end games, there really aren't any I can come up with. The Stars have to be better in all aspects, with a particular emphasis of bringing the penalty kill and save percentage back to the level they are in the rest of the season.

At some time, some way, that's going to happen. Right?