[6] That season, Real Sociedad finished second in the league that season, just two points behind Real Madrid,[6] mostly thanks to a very fruitful strike partnership with Serbian forward Darko Kovačević, such that sports journalist Phil Ball nicknamed the pair "Little and Large", in reference to the height difference between the two (Nihat's height is 1.75 m and Kovačević's is 1.87 m).

Nihat also played in the UEFA Champions League with Real Sociedad as the club was paired with Juventus, Galatasaray and Olympiacos.

[8] In June 2005, reports claimed that Nihat was linked to Russian club CSKA Moscow for €20 million Euros but the move never materialized.

[12] In his fifth and last season at Real Sociedad, Nihat made his return from injury in a 3–0 loss in the Basque derby, against Athletic Bilbao.

However, in the 2008–09 season, due to injuries again, Nihat made 19 appearances equalling 764 minutes of playing time but failed to score a single goal.

On 25 April 2011, in a match against Konyaspor which turned out to be his last game, Nihat and the new Beşiktaş favourite Ricardo Quaresma had quarrel on the pitch.

After some days, Nihat told NTV Spor that his retirement was prompted by his age limiting his ability on the pitch and admitted that returning to Beşiktaş was a mistake and ill-judged, although stated there were some beautiful moments.

[25] In Group C at the 2002 FIFA World Cup, Nihat made his only appearance as a 79th-minute substitute for Yıldıray Baştürk against Costa Rica.

Both teams were level on points, both having beaten Switzerland and lost to Portugal, with exactly the same number of goals scored and conceded, a win would guarantee a quarter-finals spot whilst a draw would mean penalty-shootouts would be required in the group stage.

[29] Nihat was ruled out of Turkey's semi-final with Germany due to a thigh injury,[30] which ultimately required surgery and prevented him from playing for Villarreal in the early part of the 2008–09 season.

On 6 July 2012, it was reported that Nihat has joined the coaching staff at his former club Villarreal as an assistant-manager of the youth team.

"Villarreal CF has opened the doors and I have always felt at home, I played three seasons here and in recent times I have followed the team as an amateur.

I want to start my new career coaching from below, like I did as a player, The president Fernando Roig has made history at this club and certainly have the ability to return to the elite as soon as possible.