Boruc spent five years at Celtic between 2005 and 2010.
Former Celtic goalkeeper Artur Boruc has posted on Instagram as Friday signalled 13 years ago since he put pen to paper on a deal to join the Scottish champions in 2005 - and some Celtic fans reacted to the post on Twitter.
The 38-year-old is currently with Premier League side AFC Bournemouth, acting as back-up goalkeeper to Asmir Begovic at the Vitality Stadium under Eddie Howe.
Boruc first joined Celtic back in 2005 on loan from Legia Warsaw for the 2005-06 season. Keeping 14 clean sheets in 32 games, Celtic opted to land the star on a permanent basis and he remained in Glasgow for four more years.
The former Celtic stopper posted on Instagram 13 years on from signing on loan with the Hoops, describing the move to the Scottish side as a "great moment".
Boruc clocked up 191 appearances for Celtic, keeping a huge 76 clean sheets and conceding just 176 goals. During his five years, he helped Celtic win three Scottish Premiership titles, two Scottish League Cups and one Scottish Cup title.
Some Celtic fans reacted to Boruc's Instagram post on Twitter, with the majority reminiscing about his time at Celtic. Some even urged the veteran stopper to return to Celtic Park.
Come back Artur! Absolute legend.— Chris (@chrisfocusmtb) July 13, 2018
Come back!— Michelle Davidson (@chelledav) July 13, 2018
Come back x— Ewan (@ewan__campbell) July 13, 2018
miss u come home— Large patrović (@Zakmcj_67) July 13, 2018
Been watching Celtic for over 50 years and without a doubt at your peak you were the best I’ve seen at our club.— Liam Brackenridge (@Brackiebhoy) July 13, 2018