Celtic sold Odsonne Edouard to Crystal Palace on the final day of the transfer window and managed to sign Georgios Giakoumakis from Dutch second division side VVV-Venlo.
Giakoumakis was the highest goalscorer in the Dutch Eredivisie last season despite Venlo being relegated from the Dutch top tier.
However, Provan pointed out that the forward is still unproven in the Scottish Premiership and there is no guarantee that he will continue to score goals in Scotland.
But he stressed that Nisbet is a proven commodity in the Scottish Premiership and was surprised that Celtic did not try to sign him.
He insisted that the forward would have scored a lot more for Celtic than he has been doing at Hibernian.
Provan said on The Go Radio Football Show: “I am hugely surprised that a deal wasn’t done for Kevin Nisbet.
“Giakoumakis has come and his numbers are good, but no one knows if he is going to hack it here.
“The one thing about Kevin Nisbet is that he has proved that can score in the Premiership.
“For me, he would have scored a hell of a lot more goals given the players Celtic would have had around him.
“He would have had more chances playing for Celtic than at Hibs. That for me was a no-brainer.”
Nisbet scored 18 times in all competitions last season and has netted once in the league already in the ongoing campaign.
