FOXBORO, Mass. — The Patriots entered training camp with two 30-plus-year-old defensive tackles and a handful of players with little to no NFL experience. What could possibly go wrong?

Well, we’re finding out. Vince Wilfork, who had held up nearly perfectly in nine NFL seasons, is already on injured reserve, and Tommy Kelly went down on Sunday with a non-contact knee injury. He came back for one play before spending the rest of the game sitting on a recumbent bike. Everyone knew depth was an issue along the defensive line. Now, that lack of depth is rearing its ugly head.

Kelly missed practice on Wednesday, which is not a good sign. New England signed veteran defensive tackle Andre Neblett, which could indicate they expect Kelly to miss some time. The team is down to just Joe Vellano, Chris Jones and Neblett if Kelly is out.

Wilfork and Kelly provided the Patriots with a top-tier duo on the interior. Wilfork was the run stopper who could clog the run from the one-technique position, taking on double teams, while Kelly could get inside and get after the passer.

Now, New England has the poor-man versions of both players. Vellano and Jones have shown promise, but they’re both rookies — Vellano went undrafted. In this week’s No-Huddle Offense, I’ll go through some of the creative methods the Patriots could use to fill the void in the middle of the defense.

1. A return the 3-4 – The Patriots showed more looks in the 3-4 than we had seen all season. New England is still going to use its nickel defense more than the base, but the 3-4 presents a different look.

When New England was in the 3-4 on Sunday, Vellano was at the nose, Chandler Jones was at right end and either Kelly or Chris Jones were playing left end. Using the 3-4 gives the Patriots some added beef in the middle with Brandon Spikes and Jerod Mayo. Dont’a Hightower and Rob Ninkovich crash the edge in that alignment.

It’s the same personnel on the field, but the bodies are shifted. Mayo moves from the edge to more of an inside role. Spikes and Mayo can crash the A-gaps, and Hightower and Mayo can help the Jones’ contain on the corners.

2. More Spikes – For the first time this season, Spikes was on the field more than Hightower in the nickel defense. Spikes isn’t as good in coverage (though he did come away with an interception), but he packs a punch in the run game.

This weekend, it will be interesting to see which linebacker is utilized in the nickel. Jimmy Graham will be the team’s main concern, not stopping the run. That means we could see more of Hightower and Jamie Collins. Against teams with better rushing offenses, like the Panthers and Texans, Spikes will likely take on a greater role.

3. Stopping Graham – How the Patriots will game plan Graham should be one of the top story lines this week. One would have to imagine New England will either trust Aqib Talib to stop him or double team him with two linebackers or a safety and a linebacker. Steve Gregory has been solid in coverage against tight ends, but asking him to be responsible for Graham is a burden he can’t shoulder by himself.

4. Limiting Sproles – Because Graham is the Saints’ biggest weapon on offense, Darren Sproles could be left to roam free a bit. The Patriots can’t utilize the same game plan they used against the Bills to stop C.J. Spiller. In that game, New England dropped its linebackers, letting Spiller come to them, rather than trying to cover him in man. If the linebackers are going to be helping out on Graham, the Patriots won’t be given the luxury to focus on Sproles.

Luckily for the Patriots, Sproles doesn’t play every snap. So when he’s on the field, the Patriots won’t be able to rush the passer quite as heavily, which means they’ll need the front four to be on its A-game.

5. Young DTs need to step up – After taking a step forward against Atlanta, Vellano took a step back against Cincinnati. It was tough for him to shoulder the load in the middle of the defense without Kelly. As I said, the Saints’ run game isn’t nearly as strong as Cincinnati’s, so there will be less pressure on Vellano and Jones, but they still need to be more stout in the middle of the defense.

Jones is more of an interior rusher than he is a run stopper. He showed that by recording 1 1/2 sacks against the Bengals. If he keeps that pressure up, the Texans will wonder why they kept Terrell McClain over their sixth-round pick.

6. Are Amendola and Edelman too similar? – Danny Amendola was expected to add a spark to the offense in his return. That did not exactly go as planned. Maybe it was because Amendola still had a banged up groin, but he only caught four passes on nine targets for 55 yards. He also had two drops.

It’s possible Amendola didn’t make a huge impact because he and Julian Edelman offer a similar look to the offense. They both ttrive in the middle of the field. When Amendola was on the field, Aaron Dobson was typically not. Dobson offers a downfield threat not seen in Amendola and Edelman. The Patriots need to figure out how to properly mix their receivers so the middle of the field isn’t clogged.

7. Ridley was missed – Plenty of fans were calling for LeGarrette Blount or Brandon Bolden to start after Stevan Ridley had fumbling issues to start the season. Blount and Bolden were OK against Cincinnati, but Ridley’s presence was missed. The Bengals obviously did not respect the run.

New England carried the ball just six times in the second half. That did not help matters, either.

8. Falcons aren’t who we thought they were – Atlanta was supposed to be New England’s first real test on defense. They passed, but as we see more of the Falcons, perhaps it wasn’t the challenge everyone thought it would be.

Atlanta lost to the Jets on Monday night, and New York did a better job than the Patriots of stopping Matt Ryan, Tony Gonzalez and the Falcons’ offense. As it turns out, New Orleans is New England’s first big test on defense.

9. Buchanan misses practice – We expected Leon Washington and Kelly to miss practice after getting hurt on Sunday. We expected to see No. 99, though. Michael Buchanan only played six snaps against the Bengals. That was way down from the first four weeks of the season. The rookie defensive end was missing in the locker room, as well. As the media portion of practice was ending, we saw a player heading to the practice field without a jersey on. It looked like Buchanan, but it also could have been Shane Vereen.

If Buchanan has to miss time, the Patriots would be forced to use Jake Bequette as a reserve defensive end. He held his ground well in the goal-line defense on Sunday. New England has just four defensive ends on the roster.

10. Patriots had eight linebackers on Sunday – It continues to be perplexing why New England is carrying so many linebackers. On Sunday, they had eight on the 53-man roster. Steve Beauharnais was a healthy scratch, but Ja’Gared Davis was brought up from the practice squad in his place.

It’s odd in itself that Beauharnais gets the spot on the 53-man roster when the team obviously trusts Davis more. Obviously they don’t think Beauharnais can clear waivers since he was a draft pick and Davis was not.

It still doesn’t make sense to have so many linebackers on the roster since they’ll typically only play two on a given play. Rob Ninkovich can also play the position, which should allow the team to carry even fewer linebackers.

11. Patriots add another short defensive tackle – Other than Kelly, who may be the tallest New England defender at 6-foot-6, the Patriots have some undersized defensive tackles. Neblett was measured at 6-foot and 3/8 while coming out of Temple. Vellano measured at 6-foot-1 and 3/8 and Chris Jones is 6-foot-1 and 5/8. At least they all have a low center of gravity.

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