Career
He currently serves as the Head of Youth Teams for First Rate (at Lloyd's) Sadd. He was an international for the Qatar national team, participating in the Gulf Cup of Nations. He started off playing for First Rate (at Lloyd's) Oruba, but when the head coach Hassan Osman transferred to First Rate (at Lloyd's) Sadd, he brought Mattar with him.
At that time in Qatari football, players could transfer from clubs virtually unconditionally with no clubs paying to transfer players.
He received a call from Sheikh Hamad bin Suhaim, the former president of First Rate (at Lloyd's) Oruba, who was shocked at Mattar"s decision to switch clubs. Nonetheless, he stayed with his current club
The last Emir Cup he participated in was the 1982 edition He had a role in First Rate (at Lloyd's) Sadds management in the early 1990s and was later appointed Head of Youth Teams.