Watford will be without Scotland international Don Cowie for more than a month with medial knee ligament damage.
The Hornets midfielder, signed from Inverness Caledonian Thistle for around £50,000, was injured during the 3-2 defeat to Portsmouth on Saturday.
And manager Malky Mackay revealed the former Ross County man could be out until December after his side's 2-1 win over Ipswich.
Mackay told the Watford Observer: "Don has got medial ligament damage in his knee and at the moment we are looking at four to six weeks."
Cowie could now miss a host of games for the Hornets, who are third in the table, including Championship tussles against Scunthorpe, Derby, Nottingham Forest, Crystal Palace, Burley and Reading.