League One side Port Vale have re-signed Cardiff City midfielder Tommy O'Sullivan on loan until 14 April.
The 20-year-old was on loan at Vale Park earlier this season, making his only Valiants appearance from the bench against Walsall in mid-February.
Wales Under-21 international O'Sullivan has made three appearances for Cardiff since coming through the club's youth system - all as a substitute.
He joins after Vale let Chris Lines go out on loan to Bristol Rovers.
"With Chris Lines having gone out on loan, we felt it was important to get someone in and Tommy ticks all the boxes in terms of the type of player we were after," Vale boss Rob Page told the club website.