In a productive first season following his summer transfer from Bournemouth, Grabban was in a hot run of form prior to the injury, scoring five in five games. This included the crucial second goal in the 2-0 derby win over play-off rivals Ipswich Town, but the day after the game Grabban felt the injury and scans showed an operation was required.
City's top scorer in the Sky Bet Championship this season is Cameron Jerome with 16 goals, and a continuation of that form is vital if Norwich are to recover from their surprise midweek 1-0 defeat at home to Wigan, and renew a promotion bid.
Also available in the striker department is Gary Hooper, who has nine goals from 13 starts this season, but has been in and out of the side.
In midfield, Jonathan Howson has made a decent contribution with four goals in 21 starts this season, but in scorching goalscoring form is another ex-Leeds United man, Bradley Johnson. His opening goal in the East Anglian derby was his tenth of the season and his third in four games.
The final goal source open to Alex Neil is the loan market. With just six points separating the top seven clubs, it is the most competitive and unpredictable promotion chase in years, and Norwich need to quickly get back on a run of form that brought them six straight wins prior to Wednesday's reverse to lowly Wigan. This may see Neil scour the emergency loans available to him in a bid to find the goals to secure a Premier League return for the Canaries at the first time of asking.