Celtic boss Brendan Rodgers has fired a warning shot to big money summer signings Gustaf Lagerbielke and Maik Nawrocki.

The two centre-backs cost Celtic £7.3m combined but both been pushed further down the pecking order by the surprise re-emergence of Liam Scales, who has nailed down a starting spot beside Cameron Carter-Vickers.

The Northern Irishman has refused to play both defenders and not included them in recent squads despite the duo being clearly fit.

Polish centre-back Nawrocki who arrived for a fee of £4.3 million has not featured for the Scottish champions since August, when he sustained a hamstring injury during the League Cup defeat to Kilmarnock. While Swedish centre-back Lagerbielke who cost £3 million last played competitively against Livingston in September.

The 50-year-old threw down the gauntlet to both players by insisting that the pair weren't showing enough in training to get the nod over their rivals to oust them out of their position. He insisted that the absence of both players was no big mystery.

READ MORE: Celtic boss Rodgers explains Nawrocki and Lagerbielke absence

Rodgers said: "I think it is always personality. I think with the young players coming in there are players ahead of them but what always catches my attention is training.

"I am out there everyday watching training and when I see players train and work with that personality then they will always edge their way closer to my thinking. I have said before our squad is quite big and there are players who have been ahead of them.

"Unfortunately for the likes of Maik and Gustaf, Liam (Scales) has come into the team and really took his opportunity. We've got Nat Phillips who has been brilliant since he has been here and has been a real positive influence and it is the one area of the team you don't really want to change too much, especially when both players are fit as it is all about the two players playing.

"For any player it is all about what they do in training as that is all you can do. You can't get too disappointed. If you are working hard then hopefully those opportunities will come for you."

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