Matt Hall attends to his team at the Central checkpoint. (Photo: Molly Rettig / KUAC)2015 Yukon Quest winner Brent Sass scratched on Sunday afternoon — just 16 miles from the Central checkpoint — because of concerns over the health of two of his dogs.Listen nowMeanwhile, extreme cold and fatigue took their toll on the remaining teams. The 75-mile run from Circle to Central, which typically takes lead teams ten hours, stretched to 16 or more into Sunday.“It’s just made for a really slow trek, Quest leader Matt Hall said.”Hall, of Two Rivers, traveled about five miles an hour up Birch Creek toward Central Sunday (Feb. 12). Hall said the slow pace was largely because of drag created by the abrasive snow, but also other factors.“Part of it’s we’re gonna be slowing down at this point in time of the race anyway,” Hall said. “We ran kinda hard it makes double sense we’d be slowing down. Even though it’s very, very faint this entire 80 miles here is uphill, it’s going up a drainage.”Hall had a big lead over 2nd place musher Hugh Neff at Central last night. Hall made the run over Eagle Summit early this morning as the temperature began warming. Allen Moore, now running 3rd, has been picking up speed after struggling with sick dogs.“They haven’t been feeling so perky up until now,” Moore said. “But they’re coming around, I hope right now.”Moore said his dogs have remained hungry through the illness.“One feeding I figured it out,” Moore said. “It was almost 30 pounds of dog food, 12 dogs.”Moore, Ed Hopkins and Paige Droby camped in Central Monday morning, resting for the big climb over Eagle Summit.