Mathis launched his professional career in Romania where he averaged 10pts and four rebounds a game in a season cut short by club financial difficulties.
He played out the last two seasons as a professional in the ABA latterly playing for South Florida Gold averaging 16pts and eight rebounds per game.
“We are happy to bring Marquis into the Sharks family and show what he is capable of contributing as a skilled big man” said coach Atiba Lyons.
“He has had a tough road to the Sharks but I am confident his hard work and determination will come through clearly and fit in well with our blue collar fans.”
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As the DBL Sharks reinforce the team roster, Coach Lyons reflected on the success of their Florida summer camp.
“He is another player I was able to coach and work with this summer and he really impressed me. He plays inside out and is a strong player who can score in a variety of ways” said Lyons.
Mathis commentedd: “Once I spoke to Coach Lyons about his camp I knew it was a great opportunity to be identified and get back into Europe. I plan on working my tail off given this opportunity and play my role on a team full of talent to ensure that Sharks are contending for a top four finish” said Mathis.
Sharks tip off against Leicester Riders on September 23.