BUFFALO, N.Y. — Michael Kesselring had a goal and an assist to help Utah beat the sliding Buffalo Sabres 5-2 on Saturday. Rookie Tyson Kozak scored his first NHL goal and Jiri Kulich also scored for the Sabres who are winless in six straight games. Key moment Sergachev’s go-ahead goal in the second came when Luukkonen was taken out of …