Dundee United midfielder Stuart Armstrong has been selected for the first time as well and there is also a place for striker Leigh Griffiths after his superb season on loan at Hibernian.
And manager Gordon Strachan has also handed recalls to Southampton defender Danny Fox and Cardiff midfielder Craig Conway.
However, veteran striker Kenny Miller is not among the 28-man squad.
Strachan said: "Kenny has been injured for over a month with a hamstring problem.
"I spoke to Kenny last week and it would be better for him to rest his hamstring. We will see him in the next squad and he's happy with that."
Regarding Griffiths, Strachan said: "Over the last couple of seasons he has decided he wants to improve and get better, and he has done that.
"At this moment he is shaping a good career. He was very close to being in the squad the last time."
Mulgrew and Commons rest
As well as Watt, Celtic are represented by captain Scott Brown and James Forrest, but Charlie Mulgrew and Kris Commons will not be making the trip.
"Charlie Mulgrew is not going to be there because he's getting married," said Strachan. "He and Kris have played a lot of games this year for Celtic.
"I've kept in touch with Lenny (Celtic boss Neil Lennon) and he feels that Forrest, Brown and Watt probably need a game and that the other two need a rest."
With regard to the first-time call-ups, Strachan added: "We've got a few new faces in this squad and it is partly looking to the future. I'm looking forward to getting them together.
"There are some exciting young players involved. Armstrong is a very modern footballer and has great positioning, I have heard great things from (Scotland U21 boss) Billy Stark.
"Jack is another exciting young player. Again, I have heard great things from colleagues like Billy and Mark Wotte.
"Greer has had a great season for Brighton, and the same with Conway at Cardiff."
Scotland squad: Gilks, Marshall, McGregor, Caldwell, Fox, Greer, Hanley, Hutton, Martin, Wallace, Webster, Whittaker, Armstrong, Bridcutt, Brown, Burke, Conway, Forrest, Jack, Mackay-Steven, McArthur, Morrison, Naismith, Snodgrass, Griffiths, Maloney, Rhodes, Watt.