A Martin Guptill drive has floored former Australian test bowler Joe Mennie in English county cricket.
Mennie, who played one test and two one-day internationals in 2016, was struck on the side of the head and fell still on the wicket as players and officials, including Worcestershire's Guptill, rushed to his aid.
The Lancashire bowler became the first player to be subbed out of a game with concussion.
Mennie reportedly deflected the ball towards his temple.
He walked off the ground unassisted after receiving medical attention during a lengthy delay.
Danny Lamb replaced Mennie under new rules instigated this season.
A fractured skull and internal bleeding from a training accident forced Mennie to miss two months of cricket last season.
Guptill went on to make 111 from 106 balls as part of Worcestershire's 361 for four. They have a lead of 478 with two days' play remaining.