EAST RUTHERFORD, N.J. – Chad Wheeler was introduced to Khalil Mack last Dec. 3 in Oakland. He does not have fond memories of the meeting.

Then a rookie free agent, Wheeler made his third career start at right tackle for the Giants. For much of the game, his primary assignment was to block Mack, the linebacker who was then with the Raiders and is on everyone's short list of the NFL's best defensive players.

Mack finished with four tackles, one of which was arguably the game's most important play. The Giants trailed, 10-7, but had a second down at the Raiders' four-yard line with 42 seconds remaining in the second quarter. A touchdown likely would have given the Giants - who entered the game at 2-9 – a halftime lead. But at the snap, Mack charged forward, knocked Wheeler to the ground, and sacked quarterback Geno Smith for a seven-yard loss. That wasn't all. Mack also grabbed and secured the football – officially forcing and recovering a fumble – to end the Giants' threat.

The Giants never did take the lead and eventually lost, 24-17.

This is all relevant, because Mack now plays for the Chicago Bears, who acquired him in a Sept. 1 trade that included two first-round draft choices going to Oakland. The 8-3 Bears will visit MetLife Stadium Sunday to face the Giants.

Despite missing two games with an ankle injury, Mack's 8.0 sacks are twice as many as any of his teammates. He is tied for the NFL lead with five forced fumbles. Mack has also recovered two fumbles.

Chicago defensive coordinator Vic Fangio lines up Mack in different spots, seeking favorable matchups. Wheeler and left tackle Nate Solder will both get their fill of Mack.

"He's a great edge rusher, he has a good combination of speed and power," Wheeler said. "He brings a lot to the table, so we've got to do the same. … He's just relentless. A great player, he has an internal drive that sometimes is unmatched, so you've got to bring it."

On Sept. 23, Wheeler spent much of the afternoon blocking Houston's J.J. Watt, the three-time NFL Defensive Player of the Year. Watt had eight tackles, including three sacks of Eli Manning for 25 yards.

"It's two different animals," Wheeler said. "They're both really good at what they do, but they do different things so you can't just do the same thing for one guy. Everybody's different."

Solder faced Mack twice when he played for New England. Mack did not have a sack in the third game of his rookie season, but did have an eight-yard takedown of Tom Brady last year.

"He's got strengths up through the roof," Solder said. "He's incredible and so you do the best you can all week, understanding what they're all about, how they like to do it and how their defensive coordinator likes to use them and then when it comes to game day, you got to play your best." Asked a follow-up question about Mack, Solder said, "He's got all the talent and qualities that you would ever ask for in a defensive end, but he plays with a really good team, too."

Solder is a former first-round draft choice who has started 122 regular-season and postseason games. Wheeler was not drafted, and has started 14 games, including the last nine. It seems likely, then, that Fangio will place Mack on Wheeler's side for the majority of the game.

"He's been challenged each week," coach Pat Shurmur said of Wheeler. "I think he's developed throughout the season, he's gotten better each week. He's with that group of guys that have played their best three games in the last three weeks against some really good opponents. … He will face both defensive ends, 52 (Mack) lines up on both sides depending on what they're trying to accomplish, but (Leonard) Floyd is also an outstanding rusher."

Of course, it's not just the tackles that have to focus on the Bears' formidable front. The players that handle the ball are well aware of the talent level Chicago will bring to this game.

"(Mack) is good as advertised," said running back Saquon Barkley, who is third in the NFL with 1,410 yards from scrimmage. "He's probably the best defensive player in the league. He's an active player, he's big, fast, strong. He's everything you want in an outside linebacker slash D-end. He's definitely going to be a challenge this week, but we played great players before and we just got to come out ready to compete and ready to work."

"Mack, he stands out," said Manning, who has been sacked 38 times, one shy of his career high. "He does a good job getting sacks, causing fumbles, interceptions – he does it all.

"I think he's got great technique. He's got great effort. He's an athlete, and just has a nose for making plays and being around the ball."

On Sunday, the Giants will commence an all-out effort to keep Mack away from it.