The New York Giants yielded 84 points while LB Michael Boley missed two and a half games with a hamstring injury last season.

That stretch included a narrow defeat to the San Francisco 49ers as well as disastrous losses against the Philadelphia Eagles and New Orleans Saints, so it wasn’t a shock that general manager Jerry Reese traded a fifth-round pick for former Bengals linebacker Keith Rivers in the offseason.

The season-opening loss to the Dallas Cowboys aside, the acquisition of Rivers paid immediate dividends as Boley was limited by another hamstring injury on Wednesday.

“Great things,” Boley told when asked what he saw out of Rivers in the first game. “He’s a baller. It shows, and that’s why we got him. That’s why we brought him here.”

Rivers finished with seven total tackles, including one on Cowboys running back DeMarco Murray that involved holding off TE Jason Witten with his surgically repaired wrist while making the tackle with his left hand.

For someone who missed the entire 2011 season with a wrist injury, Rivers should have been thrilled about the play. Instead, the former ninth-overall pick gave a window into his unusually high standards.

“I probably should have just been able to get rid of Witten,” Rivers said, adding, “It’s a situation where [Murray] should have been tackled earlier.”

Was Rivers looking at the same tape?

He was practically on an island on the play. Murray took the delayed handoff straight through the defensive line without being touched and reached the second line of defenders as Witten began to engage Rivers. So for the newest member of the Giants defense, making the play was a small miracle. It shouldn’t matter that Murray gained five yards. The fact that he went down at all is a positive.

Rivers just didn’t see it that way, and it’s that level of professionalism Reese brought to a unit that includes budding linebackers such as Jacquian Williams, Mark Herzlich and Spencer Paysinger as well as veterans Mathias Kiwanuka, Chase Blackburn and Boley.

The group is an even mix of athleticism and experience, and it’s a major departure from the 2011 campaign when the Giants struggled to find enough healthy bodies at the position for defensive coordinator Perry Fewell’s two-linebacker sub package.

Now the Giants are so flush with capable linebackers that Fewell conceded he’ll be forced to use more of the base 4-3 defense this season, and that means fans should expect to see just about all of the seven members of the unit.

“There’s plenty of room for plenty of people,” coach Tom Coughlin said Thursday, adding, “Jacquian is another guy that hopefully is going to start to play better and challenge for time because all of those guys can run and they can help us in a lot of different ways.”

Rivers said he’s not focused on competing for snaps at the position, and Boley didn’t hesitate to say that he appreciates the rotation because it “gives us a lot more free range as [far as] what we can do, different packages, different guys in different situations.”

And if it means the Giants will win more, Boley will sign up for anything.

“We could both be on the sideline,” he said, “but as long as who’s on the field is helping us win, that’s all that matters.”

Boley was limited in practice last week, so he could have a larger role given the Giants’ 10-day break before their Week 2 matchup with the Tampa Bay Buccaneers. Rivers hurt his hamstring during the game but expects to be ready for practice next week. (Rivers joked that he and Boley make "one healthy, good player," which in essence, was the point of pairing them at weakside linebacker.)

But even if both players are less than 100 percent, guys like Paysinger and Williams can easily step in and that’s the major difference between the 2012 Giants defense and the units of the last few years.

Injuries are unfortunate, but a team that plans for them can still be successful, and you can never have enough good football players.

Follow the Giants and Alex Raskin @CBSSportsNFLNYG and @AlexRaskinNYC.