The goal of this clinical trial is to investigate a new surgical approach to restore the anatomy of a ruptured Achilles tendon. We will use a new two-layer technique followed by rehabilitation and find out how it influence the patients clinical outcome, muscle and tendon structure, and function after one year and compare with a standard non-surgical approach followed by rehabilitation. Participants will be randomized to 1) NEWSUR: A new two-layer surgical technique followed by rehabilitation regime or 2) CONSER: A standard non-surgical treatment followed by rehabilitation . We hypothesize that restoring the anatomy of the ruptured mid-substance Achilles tendon using a new two-layer surgery technique followed by rehabilitation will yield a more favorable patient reported outcome (ATRS) one year after rupture compared to standard non-surgical treatment followed by rehabilitation.