The Portuguese boss was forced to use all three substitutions at half-time after lacklustre Gers fell behind to Louis Moult’s third-minute opener.
But the bold move paid off with one of his replacements Joe Garner levelling on the hour mark.
The result sees Caixinha’s side fall 11 points behind Aberdeen in the race for second but will leave him in little doubt about the work which lies ahead. Stephen Robinson’s side, meanwhile, remain in 10th.
Gers turned up the tempo against Hamilton in their first game under Caixinha a fortnight ago.
But they were well off the pace as they kicked-off against the Steelmen.
Losing an early goal did little to help the Light Blues find their rhythm but the set-back was self-inflicted.
Clint Hill was picking up Moult as Elliott Frear swept in his corner but the veteran centre-half misjudged the flight, allowing the frontman to nod home at the back post.
It should have been a wake-up call but Gers continued to look sluggish and disjointed.
Jon Toral did at least measure his through ball for Martyn Waghorn to perfection but the striker took a tumble as he went round Well stopper Craig Samson and was rightly cautioned by referee Steven McLean.
He was followed into the book by Stephen Pearson after the former Celtic midfielder lunged in on Toral. McLean was again on the scene quickly but the Ibrox faithful - already in a dark mood - let rip as he opted against taking out his red card.
It took the home side 37 minutes to create their first significant attack, but Waghorn fired wide after Barrie McKay did well to wriggle in from the left.
However, the boos which rang out at half-time only convinced Caixinha change was urgently required and he acted immediately, hooking three of his back four as skipper Lee Wallace, Hill and Lee Hodson were replaced by Andy Halliday, Michael O’Halloran and Garner at the break.
The changes - which saw Halliday and Toral move into a make-shift back three - seemed to give the hosts some extra spark and they twice came close with headers from Rob Kiernan and Garner.
Samson pushed away another headed attempt from Garner while Well’s Keith Lasley sliced wide as the hosts were opened up.
But it was third time lucky for Garner as the former Preston man threw himself at a deep cross from Miller to hook home the equaliser.
Gers’ joy almost proved to be short-lived as Moult fired the ball home after Wes Foderingham parried Ryan Bowman strike, only for the strike to be ruled out for offside.
Motherwell, though, were testing their opponents’ stop-gap back-line and Foderingham had to pull off three wonder saves to deny the visitors striking again.
Samson was also performing heroics as he palmed away Garner’s low drive while Emerson Hyndman failed to provide a stoppage-time finish.