Aston Villa and Finland goalkeeper Viljami Sinisalo, then aged twenty-one, joined Exeter City on a season-long loan in July 2023. He had previously been on loan at Ayr United and Burton Albion and, having appeared once for Finland during his time at St James' Park, won both the players' and fans' player of the year during his spell with the Grecians before returning to Villa and signing for Celtic.  

Playing for the youth set-ups of Hyvinkään Palloseura, HJK, Honka and appearing in adult football for Espoo whilst still at school, he joined Aston Villa as a scholar/trainee in 2018. Progressing from Villa’s under-18 squad to the under-23s he had a spell on loan with Ayr United during 2020/21 where he appeared in 22 league games. He followed this up with eight league and cup appearances whilst on loan with Burton Albion during the first half of 2022/23. 

Appearing also for Aston Villa under-21s in the Football League Trophy, he had come through Finland’s age group teams to under-21 level prior to making his full international debut in January 2023 in a friendly against Estonia played in Portugal. 

Joining Exeter City on a season-long loan from Aston Villa during the summer of 2023, Viljami was one of eight players to make his Grecians’ debut in the win at Wycombe Wanderers on the opening day of the 2023/24 season. Soon establishing himself as a hugely-popular first-choice goalkeeper, he went on to appear in 45 of 46 league games (missing one when involved with Finland) as well as all of the club's games in the FA Cup and League Cup. For his endeavours, positive attitude and overall contribution, Vilgami was named City's players' and fans' player of the year amongst a range of other awards.

Ranked during his season at St James' Park as Finland's third-choice goalkeeper behind two experienced players, one of whom was the national team captain, Viljami was with the Grecians at the same time as fellow Finn Ilmari Niskanen with both players frequently being in international contention starting with their joint-inclusion in the squad for European Championship qualifiers in September 2023. Sitting on the bench for internationals on several occasions during his season with Exeter, Viljami eventually made his competitive international debut in the 2-1 win over San Marino in November 2023.

On his return to Villa in May 2024, Viljami appeared for Finland against Scotland in June 2024 prior to moving to Celtic the following month on a five-year deal for a fee reported to be in the region of £1m. Arriving as an understudy to the also newly-signed Kasper Schmeichel, he quickly featured in his new club's pre-season victories over Manchester City and Chelsea in the United States and - in September 2024 - was on the bench for Finland in the Nations Cup game at Wembley when Ilmari Niskanen became the first Grecian to appear against England in a full international.