Oli signed a two-year deal with Grays in May

Oli, 23, has joined the Gills on loan with a view to a permanent move in January for an undisclosed fee.

Grays will also receive a 50% sell-on fee if the former QPR forward is sold in the future.

Griffiths, 30, who worked under Stimson at Grays, has joined the Gills on an initial one-month loan deal.

Oli also previously played under Stimson at Grays and scored 31 times in 112 games for the Blue Square Premier side.