Ipswich Town have completed the signing of defender James Wilson on a deal to January 1.
The defender has been training with the Blues since the start of July and has featured in the friendly games with Colchester, Notts County and Cambridge.
He has done enough to win a contract and could go straight into the team to face Burton Albion tomorrow afternoon.
With Luke Chambers suspended for the opening day and Toto Nsiala out until September with a hamstring injury, Lambert had been in the market for cover given the only other central defensive options were youngsters Luke Woolfenden and Corrie Ndaba.
"We have to because we're very short," Lambert said, when asked about Wilson.
"Luke (Chambers) is out, Toto (Nsiala) is out and then we've got the two kids (Luke Woolfenden and Corrie Ndaba). We need something.
"It will be short-term, that one.
"He's done really well and is a good footballer. He's not frightened to go in where it hurts. He's got experience as well.
"To go with two really young ones is a big, big ask."
Wilson began his career at Bristol City and was with the Robins until 2014.
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During his time at Ashton Gate he had loan spells with Brentford and Cheltenham Town, before joining Oldham Athletic in 2014.
He made 100 league appearances with the Latics, scoring two goals, and a move to Sheffield United followed.
He turned out for the Blades 10 times and also had a loan stint with Walsall before signing with Lincoln City in January 2018.
Capped by Wales once, the defender left Lincoln by mutual consent in June earlier this year.
He will wear the No.5 shirt at Portman Road.
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