FLORHAM PARK, N.J. -- The New York Jets can't seem to get their offensive weapons on the field at the same time.

Tight end Dustin Keller is expected to return to the lineup this week after missing two games with a pulled hamstring, but rookie wide receiver Stephen Hill is unlikely to play Sunday against the San Francisco 49ers with the same injury, Rex Ryan said Thursday.

Hill, who missed practice for the second straight day, was injured in last week's win over the Miami Dolphins. He came back to play after his injury, but that only seemed to make it worse.

The second-round pick from Georgia Tech, who started the first three games, has been a non-factor since a spectacular, two-touchdown debut. He was held without a catch in the last two games, dropping a would-be touchdown against the Dolphins.

Hill will be replaced by slot receiver Jeremy Kerley or Chaz Schilens.

At least quarterback Mark Sanchez can take comfort in knowing that Keller, his middle-of-the-field security blanket, is likely to return. Keller was limited in practice Thursday for the second straight day.

"You're talking about one of the premier receiving tight ends in the league," Ryan said of Keller, who injured his hamstring in the third preseason game. "Those guys are hard to replace ... Hopefully, Dustin will be out there this week. I assume he will be."