When the NFL added a 17th regular season game to the 2021 schedule, it was widely suspected that a number of single-season records would be in jeopardy of being broken once we finally made it to Week 18.

Now we've finally arrived at Week 18 and those suspicions have been confirmed. Four single-season records could fall over the weekend. Two were set within the last 10 years, one was set in 2001, and another record has stood for nearly 70 years.

Here's a look at all four records, who might break them and how close they are to being broken.

Most receiving yards in a single season

Current record: 1,946
Held by: Calvin Johnson (2012)
Who could break it? Cooper Kupp, Los Angeles Rams

Kupp's season has been so amazing that calling it a breakout doesn't even do it justice. He's been otherworldly, and now he's on the verge of breaking Calvin Johnson's single-season receiving yards record. He currently has 1,829 receiving yards, and needs 118 yards to break it. He'll get the chance against the San Francisco 49ers on Sunday, and since he's averaged 114 yards per game this season, it's more than possible that he'll do it.

What's incredible is that Matthew Stafford played a key role in helping Johnson set his record, and could now do the same for Kupp. Stafford was the QB for the Detroit Lions when Johnson set his record, and has been throwing passes to Kupp all season long.

Most receptions in a single season

Current record: 149
Held by: Michael Thomas (2019)
Who could break it? Cooper Kupp, Los Angeles Rams

Oh, you didn't think we were done with Cooper Kupp, did you? His incredible 2021 season is multi-dimensional, and he's poised to make even more history. He has 138 receptions on the season, and needs 12 to set the record. That would require quite a game from Kupp. He's tallied double-digit receptions five times this season, and one of those was a 13-catch game. He'll need that kind of game to break Thomas' record.

It's possible that Kupp could finish Sunday's game in possession of the elusive NFL triple crown — leading the league in catches, touchdown receptions and receiving yards, accomplished by just three other players in the Super Bowl era — and it might end up being his third-most impressive accomplishment of the day.

Most sacks in a single season

Current record: 22.5
Held by: Michael Strahan (2001)
Who could break it? T.J. Watt, Pittsburgh Steelers

Watt is very close to breaking the single-season sack record. He has 21.5 sacks, so he needs one to tie and 1.5 to break the record. And he's in that position thanks to his virtuoso performance against the Cleveland Browns in Week 17. He had 17.5 sacks coming into that game, and then managed to sack QB Baker Mayfield four times.

Those four sacks took Watt over 20 sacks in a season for the first time, and he'll have a chance to break that 20-year-old record against the Baltimore Ravens on Sunday. Lamar Jackson has been out for the last few weeks with an injured ankle, so it's possible Watt will be trying to take down the less mobile Tyler Huntley instead. There is a chance that Jackson plays on Sunday, but even if he does, the numbers are still in Watt's favor. Jackson has taken a career-high 38 sacks this season, with 14 coming in just his last four starts.

Most interceptions in a single season

Current record: 14
Held by: Dick Lane (1952)
Who could break it? Trevon Diggs, Dallas Cowboys

This one is a bit of a long shot, but even getting within tying distance of this record is an accomplishment. It was set by Dick "Night Train" Lane in 1952, when he reeled in 14 interceptions when there were just 12 games in a season.

Diggs currently has 11 interceptions (three more than anyone else in the NFL this season), so he would need three to tie and four to make the record exclusively his. The most interceptions Diggs has in a single game is two, so he'd need to have a monster performance against the Philadelphia Eagles on Saturday to make this happen. It's possible, though. Jalen Hurts has thrown nine interceptions this season, and gave up three in a single game in late November.