Ronny Deila told Dedryck Boyata to stay on his feet after the Celtic defender was sent off in the 1-1 Ladbrokes Premiership draw with Hamilton at New Douglas Park.
The Hoops were leading through a Leigh Griffiths penalty when Boyata was shown a red card by referee Craig Thomson just before the break for a last man tackle on Carlton Morris just outside the box.
In the 65th minute Accies goalkeeper and skipper Michael McGovern saved another Griffiths penalty after Thomson had penalised defender Ziggy Gordon for wrestling with Celtic counterpart Mikael Lustig at a corner.
Accies substitute Eamonn Brophy - who had scored his first Hamilton goal in the 8-1 defeat at Parkhead in January - came on for Darren Lyon in the 70th minute and levelled four minutes later with a great strike for a share of the spoils which took Celtic seven points clear of Aberdeen, who host St Johnstone on Saturday.
Asked about the sending off, the Norwegian boss said: "I think it was an okay decision.
"Rule number one, as a defender, is stay on your feet and run with people and it is something we have to learn from.
"I have seen it again one more time and I don't think he touched the ball and we have to learn from these situations.
"When you have one versus one, you have to run with people. We have to run with them instead of taking chances."
Deila claimed missed chances in the second half even with 10 men cost his side dearly.
Gary Mackay-Steven and Griffiths spurned chances, aside from the Scotland striker's penalty miss.
The Celtic boss said: "I was disappointed that we lost two points because we controlled the game quite well at 1-0, and then in the second half we produced three chances, should have scored two but we couldn't do it.
"When you get two alone with the goalkeeper and a penalty and miss it, then it is going to be hard to win football games.
"At the end, the opponents will get a chance or two and it was a good finish from the set-play."
Griffiths took his tally for the season to 33 but was left to regret the penalty miss.
He said: "I take responsibility. I've scored the first one so I should be stepping up confident of scoring the second one.
"But I've got to give credit to Michael, it was a great save and they've kicked on from that to get a point.
"But that's twice he's saved a penalty from me so hopefully I don't have to face him again.
"It's annoying that we haven't stretched our lead but we've got to accept that and take it forward.
"We just concentrate on what we do so our mind is only on Dundee on Wednesday now."
Hamilton player/manager Martin Canning felt pride had been restored after the thrashing at Celtic Park, and even expressed some disappointment that his side could not force the win.
He said: "Everyone was hurting after the last game but we showed we can get over that and put on a performance.
"We knew it was a bad night for us. Every game has to be taken individually and that proved it.
"It feels like a win in a way as we would have taken a point before the game.
"But I said in the dressing room in a quiet moment it was disappointing we didn't win given the way the game went.
"It was a big opportunity to get the three points, which would have been the most important thing.
"But I was proud of the players and the effort they put in."
Brophy, 19, had taken widespread criticism for his enthusiastic celebrations following his goal at Celtic Park.
However, he was pleased to get his second against a club who had let him go as a youngster and joked that he would like to face the Parkhead side every week.
He said: "I've only scored twice and it's been against Celtic both times.
"I wouldn't mind playing them every week.
"After my first goal against Celtic, I got criticised for celebrating too much.
"Hopefully I won't be criticised for celebrating that one.
"I was getting slaughtered off everybody. Social media, in the dressing room and pals back home slagged me.
"It wasn't so much the goal as the celebration itself.
"I understand why. It was 8-1 and when you are being beaten like that.
"But I was delighted that night because it was my first goal and I was let go by Celtic at under-15 level. It meant a lot to me.
"I know it didn't mean much in the game but this was a different story.
'I will enjoy that one much more because we got a point."