Houston Dynamo, Toronto FC draw
Dunfield headed a shot from 8 yards off the glove of Houston keeper Tally Hall, off the bottom of the crossbar and into the net.
Toronto (5-15-6, 21 points) has two ties in its past four games.
Houston (11-6-9, 42 points) got its second straight draw and is unbeaten in 10 of its past 11 games.
Will Bruin put Houston ahead 1-0 in the 21st minute, taking a pass from Oscar Boniek Garcia, cutting through two Toronto defenders and chipping a shot from 12 yards in the middle over Toronto FC goalkeeper Freddy Hall and into the net.