Reading defender Tom McIntyre arrives at Fratton Park on a 2-and-a-half-year deal.
The 25-year-old signs on a permanent deal for an undisclosed fee, though the price is rumoured to be in the region of just £75,000.
McIntyre stands at 6' 1" and had been with Reading since the age of 9, signing his first professional contract with the club in 2016.
His current contract was set to expire this summer and therefore he would have been available to sign as a free agent, however with injuries in the squad and rival clubs sniffing with their own interest, Pompey have acted to bring McIntyre in immediately.
The Scotsman made his first appearance at Fratton Park for The Royals' Under-23s side in the Group Stages of the EFL Trophy in October 2016 - That game ended 2-2.
Blues boss John Mousinho has been speaking to the club's media team about McIntyre's arrival: "Tom is a ball-playing left-sided centre-back with a huge amount of Championship experience.
"He has also captained Reading on numerous occasions and has the attributes to complement the players we already have at the club.
"As well as being comfortable on the ball, Tom is also an excellent and aggressive defender, so we're delighted to add him to our ranks." - Mousinho added.
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