Outside linebacker Manny Lawson had no setbacks at practice this week and is expected to play when the 49ers visit the New York Giants on Sunday.

Lawson missed the past two games because of a left-hamstring injury.

"I'm not going to deal with percentages," Coach Mike Nolan said. "He'll more than likely play, though."

It wasn't an easy week — at least initially — for the former first-round pick. Lawson said he thought about the injury quite a bit before practicing Wednesday and Thursday. But after Friday's workout — Lawson's first full practice this week — he is convinced the hamstring has healed.

"I have no questions about my hamstring holding up," he said.

Lawson's return comes at a time when the reeling 49ers could use some help. They not only face the defending Super Bowl champions on the road but also do so after allowing an average of 33.7 points during a three-game losing streak.

"I won't say I'm like the golden child or anything," Lawson said. "All I can say is that I will bring my 'A' game, and whatever is necessary, what I need to do, I will do. Hopefully, from the weeks that we've had and from the feelings that we've felt with these three losses, that right there will carry us to a win."

Lawson wasn't exactly dominating when he suffered a hamstring injury Sept. 28 at New Orleans. After missing all but two games last season because of a torn anterior cruciate ligament, the third-year player has just seven solo tackles and did not start against pass-oriented Seattle and New Orleans.

Lawson expects more involvement Sunday.

"They're a very physical team, coming out with two tight ends and a run game," he said.

—Before losing, 35-14, at Cleveland on Monday, the Giants were starting to look like the league's next super power. Nolan apparently didn't see it that way.

"I didn't think they were invincible," he said. "I don't think anybody is."

If the 49ers stretch New York's losing streak to two, it won't be because they copied Cleveland's X's and O's.

"We're not going to go with their offensive game plan, nor their defensive game plan," Nolan said.

—With fullback Zak Keasey (torn right biceps) out for the season, the 49ers will go with a fullback-by-committee approach Sunday.

Depending on personnel groupings, tight ends Delanie Walker and Billy Bajema, running back Michael Robinson and receiver Arnaz Battle will play fullback, Nolan said. But, the coach added, "As far as a banger goes, we have no answer to that."

—Though his secondary has encountered a rough few weeks, Nolan plans no changes.

"We just need to play better," he said.

— Offensive tackle Jonas Jennings (shoulder) will miss his fifth consecutive game, according to the injury report the team released.