Gross began his playing career at SV Höngg before moving to Grasshopper in 1965, which he left in 1976. After two years at Lausanne-Sport and two seasons at Neuchâtel Xamax, he moved to Germany in 1980 to play for VfL Bochum of the Bundesliga. In two seasons Gross made 29 appearances in the Bundesliga and scored four goals. He then returned to Switzerland and spent three years at St. Gallen, Lugano and Yverdon-Sport. Gross was capped once for Switzerland, making his debut on 8 March 1978 in a 3–1 friendly away defeat to East Germany.
Managerial career
Early career
Gross began his managerial career at Swiss side Wil in the 2. Liga, for whom he was active as player-manager. During his reign from 1988 to 1993, Wil climbed into the 1. Liga and then the Nationalliga B. While at Wil, Gross developed a reputation for an emphasis on fitness and hard work. He then joined Grasshopper as head coach in 1993. Under Gross, Grasshopper won two Swiss championships and the Swiss Cup. Gross's success with Grasshopper meant he was a very highly rated coach in his native Switzerland, but he was still little-known outside central Europe and it was a major shock when in November 1999 he was chosen to succeed Gerry Francis as manager of Tottenham Hotspur.
Tottenham Hotspur
Gross was hired on 19 November 1997, and endured a tough time; lasting nine months with Tottenham starting in the relegation zone. To further his troubles, his most trusted aide, the Swiss fitness coachFritz Schmid, who had been an integral part of Gross' training plans at Grasshopper, was denied a work permit by the British government and so was unable to take up this role at Tottenham. Gross' initial fortunes were mixed; his debut was a 1–0 loss to Crystal Palace at White Hart Lane, followed by a 2–0 win over Everton at Goodison Park, with a heavy 6–1 home defeat at the hands of Chelsea. However, despite some signs of improvement, he was relentlessly ridiculed by the British tabloids. The tabloid ridicule of Gross was often linked to his poor grasp of English and first Spurs press conference, where he arrived late from Heathrow Airport brandishing a London Underground ticket with the words: "I want this to become my ticket to the dreams". Gross' position became increasingly untenable as the 1998–99 season approached, and when Spurs lost two of their opening three matches, chairman Alan Sugar ended Gross' contract on 5 September 1998, blaming the media for destroying his reputation. He had won three of his last ten matches.
Basel
Gross returned to his native Switzerland, finding work as the manager of Basel on 15 June 1999. He worked to rebuild Basel into the premier force in Swiss football and achieved greater success than when manager of Grasshopper. Under Gross' guidance, Basel won four Swiss championships, four Swiss Cups, and mounted a fairytale run in the UEFA Champions League in the 2002–03 season, beating eventual finalists Juventus as well as knocking outCeltic and drawing with Liverpool and Manchester United. Gross' success in these games against British sides went a long way towards restoring his reputation among the British media and fans. He took Basel on another European adventure three seasons later as they reached the quarter finals of the UEFA Cup in 2005–06, before bowing out to English side Middlesbrough 4–3 on aggregate despite leading 2–0 after the first leg at St. Jakob-Park. On 17 May 2009, Gross was attacked by fans of Zürich on a tram after Basel defeated Zürich that day. He received no serious injuries. On 27 May, he was sacked after ten years at the club.
On 6 December 2009, Gross was revealed as the new manager of VfB Stuttgart. Sensationally, he guided Die Roten to qualification to the UEFA Europa League. Gross was dismissed from his managerial job on 13 October 2010 after six defeats in seven matches, when Stuttgart found itself at the bottom of the table.
Gross signed a two-year contract on 8 May 2011 to become the new manager of Young Boys, following the sacking of former manager Vladimir Petković. However, after a run of poor results, Gross was sacked on 30 April 2012.
Gross was appointed manager of Al-Ahli on 18 June 2014, but refused to renew his contract allowing him to leave on 30 May 2016. On 3 October 2016, with the sacking of José Gomes, Gross returned to the club for a second spell.
In April 2018, Gross initially signed a two-year contract with the Egyptian club Zamalek, the deal appeared to collapse in May, but it was confirmed to be a one-year deal on 3 July 2018. On 1 June 2019, Egypt Today confirmed that Gross had been fired from his position, President Mortada Mansour of the club told Mehwar TV that "Gross is specialist in failure".
Al-Ahli
On 16 October 2019, Gross returned to Al-Ahli for a third spell. On 17 February 2020, Al-Ahli terminated his contract.
