Northampton caretaker manager David Lee has been fined £500 and issued a one-match touchline ban, which he served at the weekend.
Lee accepted a Football Association charge of using language and/or behaviour amounting to improper conduct during last week's loss at Gillingham.
The 41-year-old served the ban in Saturday's FA Cup defeat by Luton.
He stepped up from assistant to caretaker manager after .
The former Chelsea defender was appointed Johnson's assistant in June to replace Malcolm Crosby, who departed in May.