After four seasons at Steaua București, he spent nine years as a professional in Spain – eight in the two major divisions, where he amassed totals of 222 games and 45 goals – representing three clubs, mostly Numancia and Recreativo.
In his first season, Roșu only featured in four league matches, but after his direct competitor was sold he blossomed into a top-flight player, scoring six goals in 31 games in the 1994–95 campaign and adding a combined 27 in his last two as the team finished third on both occasions.
Previously, in 1997–98, as Steaua again lifted the league trophy (with three goals from the player), it became the first club in the country after World War II to conquer the national title for six consecutive years.
With Roșu on board, Steaua became the first Romanian side to reach the UEFA Champions League group stage phase, in the 1994–95 edition, and he left in 2000 with 159 matches played in the first division, all with the same team.
[11] Roșu made his debut for the Romania national team on 10 October 1998 against Portugal, in an UEFA Euro 2000 qualifier (1–0 away win), and represented his country at the tournament's final stages.