Less than 12 hours after the game had finished the man who thought he would be playing for Scotland against South Africa in Durban on Saturday discovered he will be on the bench for the fourth game of the 125th anniversary tour against a Combined NSW /Queensland Country XV in Newcastle on Tuesday night.
It was at the very same stadium last June that the Glasgowe Warriors prop made his Scottish debut in the in the 9-6 win over the Qantas Wallabies.
That win, the first by Scotland on Australian soil since current Lions tour manager Andy Irvine led the victory charge in Brisbane in a 12-6 triumph in 1982, sparked a run of 10 appearances in his country's last 11 matches that confirmed him as one of their best forwards.
His return to Australia swells Scotland's representation on the Lions tour to four and the former soldier can't wait to see some action.
"Everything has happened very quickly. Scott Johnson called me out of the room and said he had a couple of things to talk about and then it was 'congratulations, pack your bags'", said Grant.
"I can't put it into words - I'm just really excited to get out there and be involved. I woke up on Thursday morning and started getting ready to play Samoa and then I was just kind of dragged away. It's just a bit overwhelming and I just want to play as well as I can and push for a Test spot.
"I'm raring to go. I've just come off the back of a good season with Glasgow and I've been in South Africa in the sun for a week. Warren Gatland said he would give people an equal chance, so I am hoping I can give a good account of myself.
"Hopefully, I can play well enough and win a Test spot, but for now it's a case of getting out there and getting the shirt on. To begin with it is just a case of getting my head around the calls and meeting everyone.
"It was great to be able to meet some of the players in small groups to begin with and they've all been very welcoming. For now it is just a case of focusing on the job in hand on Tuesday night."
As well as ringing family and friends to tell them his good news he also had to ring his fiancée, Maxine, to tell her to cancel their planned holiday to Malaysia at the end of the month.
"She was fine about - she was just happy for me. There will be another chance to take a holiday, but Lions tours don't come around very often," added Grant.
Scottish coach Scott Johnson was delighted to see Grant given his call by the Lions, even though it cost him a player two days out from a game against Samoa.
"To get another Scottish player, who we feel possesses the talent and resolve the play at the highest level - and playing for the Lions is the highest level - is great. People out there may be in for a pleasant surprise as to what a player he is," said Johnson.