Fraser Forster has warned Lukasz Zaluska he does not like sitting on the bench after the Newcastle goalkeeper completed a season-long loan move to Celtic.
The 22-year-old became Neil Lennon's 10th summer signing after a recommendation from the Celtic manager's former midfield partner, Paul Lambert.
Forster played 39 times for Lambert last season to help Norwich win the League One title, and the 6ft 7in keeper is determined to enjoy a similarly successful spell in Scotland.
"For me it was always about getting out and playing," Forster said.
"But I've said all along, even when I was at Norwich, that I wanted to be playing football. I don't like sitting on the bench.
"I'm here to provide competition and I aim to be number one. I'm going to work as hard as I can and hopefully prove to the gaffer I should be playing. I've got to prove week in, week out, if I'm playing, that I'm worthy of the shirt."