St Mirren's epic Scottish League Cup win over Rangers will mean nothing if they fail to go on and lift the trophy, says manager Jim Goodwin.

Moments after conceding an equaliser, the Paisley side edged the quarter-final 3-2 with Conor McCarthy's close-range strike deep into stoppage time.

St Mirren, having beaten Aberdeen in the previous round, face Livingston at Hampden next month for a final place.

"It was a real monumental effort from the players," said a delighted Goodwin.

"I've said to the boys there's no point doing what we've done in the last two rounds - we've knocked out two big, big clubs including the best team left in the competition - and then not going all the way.

"I'm not getting carried away and saying we will win the cup, but we certainly believe we can."

St Mirren turned the tie on its head following Connor Goldson's early opener, with Jamie McGrath levelling from the penalty spot then adding a neat second after the break.

But Goodwin admits he feared exhaustion would scupper his side's hopes when Steven Davis fired Rangers level in the closing minutes.

"I was preparing for extra-time, my boys looked dead on their feet with five minutes to go," he said.

"They are a fit bunch but put so much effort in and that goal can really knock the wind out of you. I certainly didn't expect to get a winner in the 93rd minute - but we'll take it."

Goodwin paid tribute to his players for inflicting Rangers' first defeat in the Ibrox side's 28th game of the season, while extending their own unbeaten run to 10 matches.

"To concede so early could have made it an extremely difficult night for us, but they showed great character not to let that affect them," he added.

"Brandon Mason deserves a special mention for the job he did on James Tavernier, who has been one of the best players in Europe prior to tonight. Brandon keeping him quiet was massive."

Even Goodwin's red card for overdoing his celebrations when McCarthy rammed home the winner could not dampen the St Mirren's manager's joy.

"I'm really disappointed with the fourth official," he added. "I couldn't even explain what I'd done because I can't remember - it was just sheer elation and emotion."