In a rather freakish incident, Indian pacer Bhuvneshwar Kumar on Thursday knocked down Australian umpire Paul Reiffel with a throw from the deep.
This incident occurred in the 49th over of England's first innings after debutant Keaton Jennings tucked the ball past the square-leg umpire Reiffel for a single. Bhuvi picked up the ball and threw it casually in the direction of wicketkeeper Parthiv Patel.
But the throw didn't have enough power and the ball landed on the back of Reiffel's head. The former Australian pace bowler went down immediately. The England physio and doctor rushed out to attend to the injured umpire.
The 50-year-old left the field after some first aid and was replaced by third umpire Marais Erasmus. Nitin Menon took over as the TV umpire.
Reiffel's CT scan was clear and he was advised rest by the doctors.
Another similar incident was witnessed earlier in the year during an India-Australia ODI. Aaron Finch's powerful straight drive off Ishant Sharma smashed into Richard Kettleborough's shin. The English umpire then had to be replaced by third umpire Paul Wilson.
The first session of the Mumbai Test was dominated by England, who need to win in order to keep the series alive. Jennings gave Alastair Cook's side an ideal start to the day with a century on debut.