Despite Pompey suffering the drop at the weekend Albion have chosen to allow the Scotland Under-21 international to remain at Fratton Park and wrap up the Championship season with the South Coast side on Saturday.
"We've talked about it because we wanted to keep Scott there to help Michael [Appleton] out as much as possible," Downing told the WBA website.
"Now we've had the sad news of them going down last weekend there was consideration for him to come back this week but the fact is Michael still needs him to complete the one more game - and in terms of injuries from our point of view there is no emergency to bring Scotty back.
"He will fulfil the last fixture for Michael.
"The move has been a great help for Scott."