Colin Calderwood conceded his Hibernian side did not do enough to see off Irn-Bru Second Division Ayr and deserved to be held to a 0-0 Scottish Cup fourth round draw at Easter Road.
The Hibs boss saw resolute United defending and a poor attacking display from his side force a replay at Somerset Park, slated for Wednesday, January 19.
"That's a poor result for Hibernian but we didn't deserve to win the game. It was an under-par performance. There was nothing really good enough all round - our decent moments weren't sustained for long enough," said Calderwood.
Hibs have now won two - both wins coming in November - drawn three and lost seven of their 12 games under Calderwood, who appears to be struggling to find a solution to reverse the slump.
He added: "Frustration and anger are there all the time, but it's no use telling them what they didn't do, you've got to find a way of coaching them and making them better for the next performance.
"We found ourselves coming up against a team that played with really good organisation and found a way to develop into the game."
It could even have been worse for Hibs, with Mark Brown saving from Ayr substitute Andy Rodgers in stoppage time to keep the capital club in the cup. Ryan McCann had chances in either half for Ayr, while three times Derek Riordan could have sent Hibs through.
The forward had an effort ruled out for offside after 38 minutes, helped Liam Miller's second-half volley onto the bar and then had a point-blank effort saved by David Crawford late on as Hibs failed to breach the visitors' defence.
Stranraer-born Calderwood played for Ayr in his youth and must now take Hibs, who meet Clydesdale Bank Premier League leaders Celtic next weekend, to Somerset Park for a replay.
He said: "We've got to go through and we've got to find a way to win a game. How much we've got to improve is not of great importance to me, but what we've got to do is win the game."