Czech Republic youth keeper who is one of a clutch goalies from the region at United.
The youngster completed a move from Vysocina Jihlava.
He had previously been on trial with United and was monitored for some time. Ondrej held down the no.1 position in the Under-18s and kept goal in the FA Youth Cup run to the semi-finals, before the competition was curtailed by COVID-19.
No keeper made more than his eight appearances for the Under-23s in 2020/21, the same as Matej Kovar, and he started the following campaign on the bench for the visit of Leicester City in the Premier League 2 opener.