Cameron Carter-Vickers and Alistair Johnston were both involved in Celtic training on Wednesday as preparations continued for Thursday’s Europa League clash with Celta Vigo.

The defenders were photographed at Lennoxtown ahead of the Spanish side’s visit to Celtic Park, offering encouragement after spells on the sidelines with hamstring injuries.

For Carter-Vickers, the timing is particularly interesting. The American has missed Celtic’s last three matches against Motherwell, Benfica and Hearts, with Martin O’Neill previously identifying Sunday’s trip to Hibernian as his earliest potential return.

Keep track of every knock and return with our Celtic injury news.

His involvement in training comes ahead of that timetable, although it should not be taken as confirmation that he is ready to face Celta. Getting through a session and being fit for a European match are separate hurdles.

Johnston has endured a much longer wait. The Canadian was forced off at half-time against Kilmarnock on August 9, with further assessment revealing an injury expected to keep him out for eight to twelve weeks.

That followed a frustrating previous campaign disrupted by hamstring problems, making a sustained return especially important for the right-back. Celtic supporters have had precious few opportunities to see him build any momentum over the past year.

Johnston had already been seen working through an individual programme at Lennoxtown in September. His presence on the training pitch today is welcome, but the next question is when he can get back into the matchday squad.

There is an understandable temptation to look at those photographs and hope both can go straight back into contention. Carter-Vickers’ presence in central defence and Johnston’s aggression on the right are qualities Celtic would welcome in Europe.

But with both recovering from hamstring injuries, the priority has to be getting them back for a proper run of games. Thursday would be a welcome bonus. Having them available consistently over the coming months would be far more valuable.