Worcester centre Alex Grove, Bath full-back/wing Jack Cuthbert and Glasgow Warriors full-back/centre Peter Murchie have joined the training set-up.
Winger Lee Jones has been ruled out of the game in Rome after suffering severe concussion in the loss to Ireland in Dublin.
But full-back Stuart Hogg, who has shoulder and groin injuries, centre/wing Max Evans (calf) and scrum-half Mike Blair (shoulder) were expected to train yesterday.
Centre Nick De Luca was a late withdrawal from the team at the Aviva Stadium, having failed a fitness test in the warm-up due to a hamstring injury but is making progress.
In the pack, flanker John Barclay (ribs) is another who is still under the observation of the Scotland medical team but he was also expected to take some part in training yesterday.
With so many doubts, Robinson summoned Grove, who has three caps, Cuthbert, who has one, and the uncapped Murchie.
Grove made an impressive breakthrough to the national team in the autumn internationals of 2009, when he faced Fiji, Australia and Argentina but dropped out of the picture after that. He spent a spell on loan at Edinburgh last season, and returned to the Scotland A team this year when he was part of the side who thumped the English Saxons 35-0 at Netherdale.
Cuthbert was a member of the Scotland World Cup squad last year and came on as a substitute in a warm-up match against Ireland but was not part of the final selection who travelled to New Zealand. He has played five times for Scotland A.
Murchie made his Scotland A debut last year when he came on as a replacement against Ireland.
Robinson will name his team today for the trip to Rome, where Scotland last won in 2006.