Hearts and St Johnstone will meet again in a William Hill Scottish Cup fifth-round replay after drawing 1-1 at Tynecastle.
Hearts struggled to build on the advantage created by winger David Templeton's 10th-minute goal and, after Francisco Sandaza headed against the bar and Dave MacKay was sent off for two bookable offences, Cillian Sheridan equalised after 77 minutes.
The teams, both in Monday's quarter-final draw, will now meet in a replay at McDiarmid Park on February 14.
Saints boss Steve Lomas' frustration with referee Craig Thomson was evident throughout, but his side were also fortunate to avoid conceding a penalty when Mackay survived a handball claim early in the second half.
Peter Enckelman saved a Ryan McGowan effort low to his left before he was beaten after 10 minutes. The ball was pushed forward to Templeton, who accelerated into space before hitting a low right-footed drive into the net.
The visitors were continually searching for a route through or around Hearts, who were robust in defence, with Sandaza and Davidson in particular feeling the impact of some tough tackling. Sheridan was introduced at the interval for David Robertson, joining Sandaza up front, and had a rapid impact with a cross from the left which Sandaza headed against the bar.
Hearts had a penalty claim turned down when McGowan and Mackay challenged in the air to meet a long Andy Webster free-kick and the ball appeared to strike the Saints defender's arm. Ian Black became the first Hearts player to receive a yellow card, for dissent, before Saints were reduced to 10 men.
Mackay's acrobatic attempt to reach the ball caught Templeton and he received a second booking and a red card, leaving Saints a goal and a man down with 17 minutes to play.
Sandaza scuffed another opportunity when through on goal against Jamie MacDonald as the visitors spurned the first chance to defy their numerical disadvantage.
But moments later Sheridan beat the offside trap to run onto a Sandaza pass and apply the clinical finish to equalise.