Jose Mourinho has made an unanticipated arrival at the employment tribunal involving former Chelsea team doctor Eva Carneiro on Tuesday.
Carneiro left Chelsea in September following an argument with Mourinho on the opening day of the season and has since claimed constructive dismissal against the club.
The recently appointed Manchester United boss was not due to give evidence until Monday, but arrived at London South Employment Tribunal on Tuesday, shortly before Carneiro was due to commence her testimony.
The former Chelsea doctor turned down an offer of £1.2 million in order to settle the case, according to documents submitted on Monday, claiming Mourinho directed a Portuguese insult at her after she and physiotherapist Jon Fearn entered the field to treat Eden Hazard late in the 2-2 draw with Swansea City in August.
Mourinho was livid as the duo's actions resulted in his team being reduced to nine players - goalkeeper Thibaut Courtois was sent off earlier in the game - labelling the pair "naive and impulsive" before they were withdrawn from first-team action.
Mourinho, who was sacked by Chelsea in December after a dismal start to their Premier League title defence, was cleared of using discriminatory language towards Carneiro by the Football Association, but still faces the personal legal claim lodged by the medic.
The hearing remains ongoing.