MELBOURNE veteran Heritier Lumumba has suffered another head knock in his comeback game from concussion and is facing more time out of football.

Making his return from a long lay-off due to concussion symptoms for Casey Scorpions against Richmond in the VFL on Sunday, Lumumba suffered the knock towards the end of the third quarter.

The club has confirmed the 29-year-old will be given at least this weekend off football while the Scorpions have the bye.

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Football manager Josh Mahoney said the Demons would follow normal concussion protocols with Lumumba before deciding when he would next take the field.

"This concussion will be treated as a normal episode and we will implement our usual concussion protocol, which is two or three days of rest, until symptoms are at baseline. He will be assessed thereafter."

It's the latest setback in a frustrating season for the former Collingwood premiership defender, who hasn't played senior football since round six.

The Dees have carefully managed Lumumba and young teammate Angus Brayshaw, who copped two separate concussion problems in three weeks earlier in the year.

Brayshaw spent a month out of the game after his second incident and played his second game back in the VFL on Sunday, when he was named in the best players.

Concussion will be a hot topic again this week, with St Kilda's gun No.1 draft pick Paddy McCartin suffering his third head knock this year against Gold Coast and set to miss at least this weekend's match against Essendon.