EAST RUTHERFORD, N.J. (CBSNewYork)Giants defensive coordinator Steve Spagnuolo was wearing a smile when he addressed reporters at minicamp Wednesday — and after the team’s defense-heavy free agent spending spree, who can blame him?

After finishing last in total defense in 2015, the Giants opened up their wallets to sign defensive end Olivier Vernon, cornerback Janoris Jenkins, defensive tackle Damon Harrison and linebacker Keenan Robinson. They also used their first-round draft pick on Ohio State cornerback Eli Apple.

The additions have Spagnuolo feeling more confident.

“We’re going to be better,” he said. “We’re going to be better because of our players. We’re going to be better because of better coaching, less mistakes. We’re going to be better because it’s the second year in the system. That’s what we fully expect to do.

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“This league is about players,” he also said. “The more top-notch players you can have, I think the better defense you’re going to be. To me, it doesn’t matter what scheme you put in, how much scheme you have. Players make plays.”

One potential concern about adding so many new faces at once is whether the defense can jell together quickly enough. Spagnuolo said so far, so good.

“I kind of watch the interaction of how they are and what they’re saying on the sideline, and I think all three of those guys — Damon, OV (Vernon) and Jack Rabbit (Jenkins) — all have just kind of come in, fit in really well,” he said. “They’ve run with it. They haven’t been afraid to voice their opinion, which is a good thing. I think the transition for them … has been pretty smooth.”

Spaguolo said he’s been “pleasantly reaffirmed” that Jenkins is a “competitive, top-notch guy that doesn’t back away from anything.”

He also spoke glowingly of Vernon and why the team felt he was worth his five-year, $85 million contract.

“Because all of the offensive coaches thought that he was the toughest player to play against last year,” Spagnuolo said. “I thought that said it all. And you put on the tape, and he’s one of those guys that’s got a high motor. And he makes a difference in the football game.”

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He said Vernon’s presence could also help improve Jason Pierre-Paul’s production.

“You ask offensive coaches if there’s only one guy on the other side of the ball that scares him, I think it’s pretty easy to find a way to take him out of the game, to double him, whatever,” Spagnuolo said. “You’ve got two, it’s a little bit more challenging.”

And of Apple, the defensive coordinator said: “I do see a competitive guy there. I think if you’re going to play that position in this league, that’s the first thing you’ve got to have. And I think some of the guys around him have confidence in him. He’s made a lot of plays out there.”