Sebastian's distinguished soccer career began in Austria at the age of 3, culminating in his first professional contract at 16. He later advanced his career in the United States by joining the Division II program at Lewis University. During his tenure there, Sebastian played a pivotal role in the team's consistent success, which included annual NCAA Tournament qualifications, a regular season title, a tournament championship, and a regional championship, along with numerous team and individual accolades.
In addition to his collegiate achievements, Sebastian earned the NPSL Goalkeeper of the Year award and further honed his skills during two seasons in the USL 2. Dedicated to the growth and development of athletes worldwide, he actively works to connect with and mentor aspiring talent, helping them explore new opportunities to reach their full potential.