In the 2012–13 season, Rudņevs became the first Latvian football player in the Bundesliga. Hamburger SV started the season with three consecutive losses with Rudņevs gaining only one assist. Rudņevs scored his first goal in the Bundesliga on 26 September 2012 in a 2–2 draw against Borussia Mönchengladbach. In his first season with Hamburg Rudņevs appeared in 34 league matches, scored 12 goals with four assists, finishing as Hamburg's joint top scorer alongside Son Heung-Min, who also netted 12 times. However, his form dropped, and Rudņevs lost his place in the starting eleven early in the 2013–14 Bundesliga season.
