Answer
Nalbandian reached four Grand Slam semifinals throughout his career. He made it to the semifinals of the 2002 Wimbledon Championships, the 2003 French Open, the 2004 Australian Open, and the 2006 Wimbledon Championships. He was unable to advance to the final in any of these tournaments, losing to Lleyton Hewitt, Juan Carlos Ferrero, Roger Federer, and Rafael Nadal, respectively.