By Tzvi Machlin The sensational career of former Pro Bowl center Alex Mack came to an end today as the NFL star announced his retirement. Reports that Mack was retiring first emerged yesterday. But on Friday, he made the move official with an announcement that he was calling it a career after 13 seasons. Mack was a seven-time Pro Bowler in 13 years between the Cleveland Browns, Atlanta Falcons and San Francisco 49ers. He was a three-time All-Pro selection and was voted to the 2010s All-Decade Team too. NFL fans are wishing Mack well in his future endeavors. Many are sad to see him go given tha…