The 49ers will see Khalil Mack up close on Sunday when they take on the Bears, but they thought four months ago that they were in a position to put Mack in a 49ers uniform — and the Raiders probably wish that was the trade they had made.

As 49ers General Manager John Lynch explained last month, he tried hard to acquire Mack in a trade with the Raiders. Lynch actually said the offer he made was better than the offer the Bears made, but the Raiders went with the Bears’ offer. Lynch wondered if the Raiders didn’t want to trade Mack to the Bay Area’s other NFL team.

That might have been a consideration, but a bigger issue was probably that the Raiders didn’t really see the 49ers’ offer as better than the Bears’ offer. Lynch didn’t say exactly what the 49ers offered for Mack, but assuming it was approximately the same package of draft picks that the Bears ended up giving the Raiders, it’s possible that the Raiders turned the 49ers down simply because the Raiders expected the Bears to be picking higher in the draft order.

And, at the time, that would have been a reasonable assumption. In August, before the Mack trade, the Las Vegas odds pegged the Bears as a 6-10 or 7-9 team this season, and the 49ers as an 8-8 or 9-7 team this season. It was reasonable for the Raiders to think that if both the Bears and the 49ers were offering their first-round draft picks, the Bears’ offer was better.

That turned out to be very wrong: The 49ers are 4-10 and still in contention for the first overall pick in the draft, while the Bears are 10-4 and will send the Raiders a pick no higher than No. 21, and probably more likely in the high 20s or even the 30s. Of course, we can never say for sure what would have happened if the Raiders had traded Mack to the 49ers (the 49ers may have won more games, and the Bears may have won fewer games), but it’s unlikely that Mack would have made such a big difference as to turn the 49ers into a playoff team and the Bears into a team vying for the first overall pick.

So when Mack lines up against the 49ers on Sunday, Lynch won’t be the only one wondering what might have been. Jon Gruden may also see that game and wonder if his team would be in better shape going forward if he’d traded Mack to San Francisco instead of Chicago.