The Belfast Giants fell to their eighth successive Elite League defeat on the road as the Sheffield Steelers grabbed the winning goal 16 seconds from time.
The game stood at 3-3 when Michael Forney netted the decisive score on 19:44 in the final period.
The Giants had led in the first period through a Mark Garside goal but the hosts hit back to lead 2-1.
Belfast twice got equalisers through Mark McCutcheon and Ray Sawada but they were to go home empty-handed.
Mathieu Roy and Colton Fretter (2) got the other goals for the Steelers who are making a determined challenge for the league crown.
Sheffield, with a game in hand, are just one point behind leaders Braehead who crashed to a 6-0 defeat away to Nottingham Panthers on Saturday.