Dream ace Eddie Alvarez will not be able to keep his appointment with ZST standout Naoyuki Kotani in a lightweight contest scheduled to main event Extreme Challenge “War at the Shore” on Jan. 23 at the Tropicana Hotel and Casino in Atlantic City.

Alvarez (15-2) sustained a leg injury during his brief encounter with submission expert Shinya Aoki at K-1 “Premium Dynamite 2008” on New Year’s Eve and has been forced to withdraw. The wily Japanese groundsman ensnared Alvarez’s leg in the bout’s opening moments, forcing the tapout to a heelhook at 1:33. The loss was Alvarez’s second to date.

Though an MRI has revealed no tears or other substantial damage to Alvarez’s knee, the popular Philadelphia-bred fighter said ligaments are “looser than they should be” and he will take the time to recuperate properly, he told Sherdog Radio’s “Beatdown” on Wednesday.

Alvarez (15-2) said if the bout had come a month later he would have been ready to compete.

Extreme Challenge promoter Monte Cox, who also manages Alvarez, said the bout between Alvarez and Kotani will likely be rescheduled for a later date at the same venue. Cox is currently making final arrangements for a new main event.

The 24-year-old dynamo had a banner year in the sport, tallying four victories in a row before he reached Aoki. Two of those wins came to top-caliber competition in Dream lightweight champion Joachim Hansen, who Alvarez decisioned in May, and Tatsuya Kawajiri, who was stopped on strikes in a heated contest for Dream in July.

Alvarez is still under contract for one more fight with Dream, and will enter Bellator Fighting Championships’ eight-man lightweight tournament in April. The newcomer promotion will broadcast 12 weekly events on a one-day tape delay on ESPN Deportes.

Lotfi Sariahmed contributed to this report.