Rangers beat rivals Celtic for the second consecutive weekend as Ryan Naderi's strike earned a 1-0 away win that enlivens the Scottish Premiership title race.
Celtic still lead the table by two points, but the momentum is all on Rangers' side after two big Old Firm wins in eight days.
Derek McInnes's men blew away their old rivals to win a League Cup tie 3-0 at Ibrox last weekend as he becomes the first manager since 1991 to win his first two Old Firm encounters.
"We knew we'd have to overcome a wounded Celtic team. We played with a lot of confidence," said McInnes.
"I'm disappointed we didn't add to the goal we did score because we were deserving of that."
Celtic also suffered an awful start to their Europa League campaign with a 3-1 defeat to Ferencvaros on Thursday, with questions now raised over whether Martin O'Neill will survive an upcoming three-week international break still in charge.
"It's time for a bit of self-reflection," said 74-year-old O'Neill.
"There are always big questions when you lose football matches. You have to accept responsibility, which I do. Remember, this is the team, this is my team. I am responsible for that."
O'Neill made sweeping changes in both personnel and formation and the home side may wonder what might have been if a bright start had been rewarded.
Austin Trusty's volley into the top corner was ruled out after Liam Scales strayed offside in the build-up before Kieran Tierney smashed against the crossbar.
However, Rangers took control after they went in front on 31 minutes.
Full-Time at Parkhead
— Rangers Football Club (@RangersFC) September 20, 2026
💙 Another Old Firm Victory!
Celtic 0 - 1 Rangers pic.twitter.com/PTW6ylHJBu
Kim Min-su's strike from the edge of the box was parried by Viljami Sinisalo into the path of Naderi, who tapped into an empty net.
Djeidi Gassama hit the post as Rangers threatened to add a second before halftime.
Despite there being no away fans allowed to attend, Rangers dominated the second half and should have added to their lead.
Olwethu Makhanya's stunning strike was disallowed after the South African handled in controlling the ball.
Rangers, though, needed only the one goal as a Celtic side lacking inspiration rarely threatened to hit back and were met by a chorus of boos from the disgruntled 60 000 home fans at full time.