GREEN BAY, Wis. — Khalil Mack didn’t waste much time making his new team look pretty smart.

Mack had a debut for the ages for the Chicago Bears in Sunday’s game against the Green Bay Packers, with a strip sack in the red zone and a pick-six that sprung the Bears to a stunning 17-0 halftime lead.

Of course, part of that score came because of the injury to Packers QB Aaron Rodgers, who was hit by the Bears’ Roy Robertson-Harris on the biggest play of the game in the second quarter. Mack just missed getting in on that sack, too.

Robertson-Harris also forced DeShone Kizer — Rodgers’ replacement — to throw a weak pass right into the arms of Mack, who returned the interception 27 yards for the score and a 17-0 lead before the half. Mack nearly was tackled at the goal line by the Packers’ Davante Adams but held on.

It was Mack’s second career interception in the NFL. Both were returned for touchdowns. The last one was during Mack’s brilliant 2016 season with the Oakland Raiders, when he was named the NFL’s Defensive Player of the Year.

Why the Raiders traded Mack is still a point of contention, although the team clearly didn’t want to meet his lofty salary demands. The Bears, however, were more than willing to dish out a six-year, $141 million deal before Mack ever played a snap for his new team.

Their faith was rewarded quickly. For all the talk about how much Mack might be kept on a pitch count in his Chicago Bears debut, it didn’t last long for that plan to be ditched. Aaron Lynch started in place of Mack at left outside linebacker and played the first three snaps of the game there.

Enter Mack on the fourth play from scrimmage, and his presence was felt immediately. He pressured Rodgers on an incomplete pass and appeared to be in good physical condition. The Packers then were called for a holding penalty on Mack’s second snap.

After taking one snap on the Bears’ second defensive possession, he remained on the field for nearly the entire rest of the first half. Mack played 21 of the Bears’ 28 defensive snaps, by our count, in the first half, as he, Lynch and Leonard Floyd rotated at the two outside linebacker spots.

Mack, however, only lined up on the left side. In one interesting alignment, Floyd stood up behind Mack (who was rushing from a three-point stance) and appeared to make the Packers’ blockers hesitate a moment. Although Mack had a shot at his second sack of the first half on the play, he whiffed and rookie linebacker Roquan Smith — on his first NFL play — cleaned up the mess for his first ever sack.

In the second half, the Bears rested Mack for nine of the 12 defensive snaps on the Packers’ opening field-goal drive, with the Packers cutting the Bears’ lead to 20-3. But he played the majority of the next series, helping force Rodgers — who had returned to the game to start the second half — into an intentional grounding call.

Rodgers got the Packers cooking again, though, with six straight completions on the drive, including a gorgeous fade to Geronimo Allison for a 39-yard touchdown to make the score 20-10 Bears early in the fourth quarter.

With the Bears’ offense struggling roundly after their first two highly successful drives of the night, going three-and-out twice in a row and three times in four drive, this game was left in the hands of the defense to close out. Rodgers his Adams for a 51-yard pass and had the Packers knocking on the door again. It was clear what their game plan was: get the ball out of Rodgers’ hands quickly so Mack couldn’t keep disrupting the Packers’ offense.

Then Rodgers hit Adams for a 12-yard touchdown, and just like that Green Bay had cut the lead to 20-17. The Bears finally moved the ball on their ensuing possession, ran down some clock and helped use up all of the Packers’ timeouts. A Cody Parkey field goal upped the Bears’ lead to 23-17 with 2:39 left.

Mack and the Bears’ defense knew what it was up against. Rodgers had completed only 3-of-7 passes for 13 yards with two sacks in the first half before getting hurt. But he had ripped the Bears for 16-of-19 passing prior to the final drive, with 198 yards and two scores. It just felt like he was going to do something.

When the Bears’ Kyle Fuller missed a should-be game-ending pick, that feeling only grew — after all, you don’t give Rodgers second chances, right? He hit Cobb on a wild 75-touchdown right up the gut to take the lead at 24-23, with Mack unable to chase him down at the last minute.