Rangers skipper Barry Ferguson rued his early miss after his side were held to a 1-1 draw by Celtic at Ibrox.
The unmarked midfielder volleyed over from six yards as the Gers failed to cut their 16-point deficit on the Bank of Scotland Premier League leaders.
Brahim Hemdani's deflected long-range effort rescued a point in the closing stages after Thomas Gravesen had put the Hoops ahead before the break.
Ferguson said: 'If I had scored my chance I think it would have been a different outcome.
'I'm not used to having time to think, when I go through I'm normally running on to a ball.
'I'm just happy we got a point. At least we showed a bit of spirit - that is what is needed if you want to play for Rangers.
'A lot of new players coming in needed time to settle. I think the last few weeks, apart from the Falkirk game, we have shown a bit of form and commitment.
'Sixteen points is a massive gap. I will certainly keep fighting. It's not over yet.'
Opposing captain Neil Lennon felt he should have had a penalty moments after Gravesen's opener.
The veteran was brought down on the byline by Steven Smith but referee Kenny Clark gave a goal-kick.
Lennon told Setanta Sports: 'I think Kenny was the only one in the ground that didn't see it was a penalty.
'He took me right out. Maybe the ball was running away from me a wee bit but it's in the box - it was a definite penalty.'
His manager Gordon Strachan believed the decision was the turning point.
He said: 'Let's be fair, it's not even a debate - it was a penalty.
'And 2-0 would have been a hard mountain to climb.
'Nineteen games we have played this season and no penalties. That's some record when you're top of the league and attacking all the time.'
Strachan did agree Rangers deserved a point on the balance of play.
He added: 'We had a good first half. I thought we were good until Jiri (Jarosik) tired.
'He got a bang on his chest and found it hard to breathe.'
Gers boss Paul Le Guen felt the performance showed his side's continued improvement.
He said: 'We showed great team spirit and great courage to come back.
'We never gave up and it is a good sign. We tried and tried and we were rewarded.
'I think we are better now than two months ago. The team is more settled. There is a better team bonding.
'There is a long way to go. It is most important to carry on and be aware that when we are together we are hard to beat.
'We showed we can compete with them (Celtic) and it's important to feel the team is improving.
'I believe that it will be better and better.'