EAST RUTHERFORD, N.J. — What a difference a year has made for the Giants offense and defense.

Starting with the good, it was one year ago around this time that co-owner John Mara famously declared the Giants 28th ranked offense as being “broken.”

The Giants set out shortly thereafter to fix the offense, starting with the addition of Ben McAdoo to replace offensive coordinator Kevin Gilbride, who retired.

McAdoo’s system, which he has always maintained is a combination of input from all of the Giants’ offensive coaches and which consists of some of the old system’s principles as well as elements from the West Coast offense, turned out to be just what the doctor ordered.

The Giants offense finished 10th in the league, averaging 367.2 yards per game. The unit also upped their scoring from the previous season, finishing with 380 points this year, up from 294 from a year ago.

“Offensively, we made great strides from the beginning of the year where a lot of things were different,” quarterback Eli Manning said. “The timing from me and the receivers was off.

“We struggled, and (last Sunday) and the last few weeks, we were doing some really good things, making big plays and moving the ball.”

After initially struggling to adapt to the new terminology and concepts, many of which were foreign to Manning, things began to click as the season began to wind down.

Manning finished 2014 by reaching several milestones, including a career-high completion percentage (63.1 percent), his second-highest touchdown total (30), and the second-highest passing yardage total in a season (4,410).

“I played better than last year,” Manning said. “I felt good in the offense. I felt we had opportunities to win a lot of games, but we’ve got to win those games.

“I’ve got to play better; the team and the offense have got to play better in those moments to win those games.”

With the offense headed in the right direction, Manning believes that the Giants are only warming up.

The Giants’ passing game, which finished seventh in the league (267.0 yards per game), exploded thanks to the arrival of rookie receiver Odell Beckham Jr.

The Giants first-round draft pick, who missed the first four games of the season because of a hamstring injury, finished as the team leader with 91 catches on 1,305 yards and a team-leading 12 touchdowns, while posting nine straight games of 90 or more receiving yards.

With Victor Cruz due back from his season-ending knee injury to join Beckham and Rueben Randle, and with hopes of having a healthy duo of Rashad Jennings and Andre Williams at running back, Manning and the Giants are looking for even better production in year two of the offense’s rebuild.

“If we can come back and start where we are right now and continue to make progress, I think we’re just kind of scratching the surface of where we can get to,” Manning said.

It’s been the exact opposite for the defense, which last year finished ranked 10th overall in the league, only to fall to 29th this season.

That’s disturbing, considering the Giants spent significant money on new contracts for cornerbacks Walter Thurmond and Dominique Rodgers-Cromartie, defensive end Robert Ayers and linebackers Jon Beason and Jameel McClain.

However, injuries struck down three of those big-money contracts — Beason, Ayers and Thurmond, all of whom ended the season on injured reserve.

Rodgers-Cromartie gutted out the season by dealing with a back and hamstring issue, while staples such as cornerbacks Trumaine McBride and Prince Amukamara were lost for the season as well because of injuries.

“You can’t have 22 guys go on IR,” Beason said. “Before you can have a great team and go out and win games, you have to stay healthy. We’re not making excuses — next man up for sure — but you just can’t win that way.”

Injuries aside, the Giants were particularly vulnerable to giving up the big play. The Giants pass defense gave up 62 passes of 20-plus yards, tying them for third-most in the NFL.

The run defense wasn’t much better, allowing 17 runs of 20-plus yards, the second most in the NFL.

“I think we gave up way too many big plays in the beginning of the season,” safety Antrel Rolle said. “That is something we must work on.”

The big-play issue along with the drop in rankings could ultimately result in some changes made on the defensive side of the ball, starting with defensive coordinator Perry Fewell.

“I think it all works together, with coaches and players,” Rolle said. “I think defensively we had a lot of key injuries and at the same time, there were times where we probably could have been in better situations as coaches and players. Us players made the plays when the opportunity presented itself.”

Coach Tom Coughlin hasn’t made any decisions regarding Fewell or any of his other assistant coaches as of Tuesday, but he was quick to defend Fewell.

“Perry had his hands full, there’s no doubt about it,” Coughlin said, explaining that he was trying to look at both the good and bad in evaluating Fewell and the defense.

“We have some issues, no doubt, and you’d like to be able to think we can solve them, but you can look at the other things, too.”

Despite the issues, Mara and general manager Jerry Reese don’t believe the team is that far away from being a competitor again.

“Obviously I am very disappointed about this past season; sick about it, as a matter of fact,” Mara said. “With that being said, I do think there is some reason for optimism going forward.

“We had some young players really develop who we are excited about. We have had two pretty strong drafts in a row that we feel good about. We were still 6-10, so obviously we have a lot of work to do.

Reese added: “I don’t think we are that far away because I do think we have a nice mix of young players along with some veteran players that we can get to where we want to go.”