Rusnak, 20, was born in the Czech Republic but started his career in Slovakia with Kosice, before making the move to Manchester City at the age of 14.
Much like many young players at City though, Rusnak failed to even make an appearance for City, with his only impact in English football coming loan spells with Oldham Athletic and Birmingham City.
Another loan move followed last summer, joining Dutch side Cambuur, but after four goals and two assists in half a season, their Eredivisie rivals Groningen snapped him up on a permanent deal in January.
Since that move, Rusnak has added another six goals and four assists to his name, as his reputation in the Netherlands continues to grow and grow by the week.
Naturally, Rusnak's exploits have now sparked transfer rumours, with the Daily Mirror suggesting that Manchester City want to bring Rusnak back to the Etihad Stadium, as well as four other Premier League clubs.
Aston Villa, Newcastle United, Southampton and Swansea City are all credited with an interest in the report, with Rusnak already being lined up for a return to the Premier League.
Groningen will no doubt want to keep hold of the Slovakian having only bought him in January, but with Premier League league interest, it may be difficult to prevent a return to England for Rusnak.