Morton will battle for Scottish Championship survival in the play-offs after a goalless draw at fellow strugglers Arbroath in which they were reduced to 10 men.
With Ayr securing a 2-2 draw at Inverness, The Ton finished second bottom on goal difference.
In a first half of few chances, Nicky Low shot over for the hosts, who stayed out of relegation trouble by a point.
Thomas O'Brien was off target with a header for Arbroath in a second half which saw Morton reduced to 10 men after Sean McGinty was dismissed for violent conduct in the 66th minute.
