Defense has been a major issue for the Islanders, as the team ranks 28th in the NHL in goals allowed per game at 3.27 per. That’s a stark difference from last year, when the team allowed 2.79 goals per game, good for 21st. The Islanders have surrendered two goals or less in a game six times and are 4-1-1 on the year in those games. Outside of that, they’re 4-12-2.Today their bedraggled defense may have taken another serious hit, as Andrew MacDonald was reportedly hurt in practice.For Thomas Hickey, who was hurt blocking a shot on Saturday night in Philadelphia, the news is better than it could have been. After today's practice at the Coliseum, Coach Capuano called Hickey's condition "day-to-day".With Lubomir Visnovsky out, Hickey has been the Islanders best defender in terms of possession. Heck, he's actually been the team's best skater based on possession. Hickey has a corsi% of 54.9% at 5-on-5, which bests everyone else (min 12 GP). That means that when he's on the ice at even strength, almost 55% of the total shots taken go towards the opponent's net rather than the Islanders' net. If we move out to a smaller sample, minimum 6 GP, Thomas Vanek is the only player that bests Hickey.Earlier this season, Visnovsky suffered a concussion and has now missed about a month’s worth of games with no speedy return in sight. More nebulous is Brian Strait’s injury, which has kept him out a few weeks. With Hickey and MacDonald's statuses cloudy, the Islanders could be missing up to four defenders off of their opening night lineup when they return to the ice Wednesday. And to add to that, there's also goaltender Evgeni Nabokov on the shelf with an injury. For what it's worth, Bridgeport's defense is a bit banged up as well. Andrey Pedan and Joe Finley are both out with injuries.