Ferguson back on field; Lehan out; London fined.

Byline: Harvey Fialkov

Oct. 24--Dolphins nose tackle Jason Ferguson was back on the practice field Friday and seems likely to play Sunday against the Buffalo Bills.

While Ferguson attempts to play through a painful oblique injury, the Dolphins placed oft-injured cornerback Michael Lehan on injured reserve Friday, and re-signed cornerback Joey Thomas. Lehan, who has never been completely healthy since spraining his right ankle during an April minicamp, tweaked his hamstring in Thursday's practice session. He is now out for the season. "From our standpoint, we need consistency. We need healthy people," Dolphins coach Tony Sparano said. "There were a …