Cambridge United have re-signed striker Barry Corr on a three-week non-contract basis while Northampton's Billy Waters has joined the League Two club on loan.
Corr, 32, scored 14 goals in 31 games for the U's in his first spell but was released in June after injury problems.
"Both parties will review the position at the end of January," said head of football operations Ben Strang.
"The club and Barry are taking this one step at a time given the challenges he has faced in the last 18 months."
Waters, 23, joined the Cobblers in June from Cheltenham but has not scored for the League One side in 23 matches.
However, he scored 16 times in 55 appearances for the Robins last season.
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