Gillespie, who has won 86 caps, is currently without a club after having his contract at Sheffield United terminated by mutual consent.

That lack of game time has led to the 33-year-old winger's omission from the squad for the World Cup qualifier against San Marino on February 11.

However, Worthington has promised to review Gillespie's situation after this fixture once he finds a club.

Now a free agent, Gillespie is currently weighing up two to three options, including interest from Australia.

Worthington said: "I have taken the decision to leave Keith out because I feel it is in the best interests of everyone.

"He is not training with a group on a daily basis and that is hardly an ideal scenario.

"We will monitor his situation and see where he finishes up; what team, what country and at what level.

"Then we will take things from there. The door is still open for Keith, that's for sure."

Birmingham midfielder Damien Johnson returns to the squad after an 11-month absence through injury.

The 30-year-old had back surgery in the summer, and Worthington said: "He is looking good and is a lot stronger now.

"Damien is a great professional and to have his kind of experience around the group is very valuable.

"He has had his fair share of injuries but his attitude has always been first class."

Worthington has recalled influential trio Aaron Hughes, George McCartney and Steven Davis after they missed the defeat by Hungary in a friendly at Windsor Park in November.

Manchester United defender Jonny Evans has been included despite being sidelined with an ankle injury.

Worthington said: "I spoke to Jonny this morning and he was a little less optimistic than he was last week.

"It is 60-40 against him making it at the moment but we will keep monitoring the situation."

Celtic pair Niall McGinn and Pat McCourt - who won his only cap in 2002 when at Rochdale - have also been called up for this away fixture.

Worthington added: "I am looking forward to working with the players again as we were not up to scratch against Hungary.

"The nice thing since that game, however, is that more players are playing regular football, which is a big help."

Meanwhile, Worthington has praised Dean Shiels after the midfielder secured a move to Doncaster from Hibs.

Shiels had an operation in 2006 to remove his right eye after being blinded in a childhood accident.

He has been named in the squad to face San Marino and Worthington said: "Dean dealt with the situation regarding his eye in superb fashion.

"He has a good attitude, works hard and this is a nice move for him. It also means we can keep a closer eye on him in England."