49ers' Brock Purdy did manage to end one Patrick Mahomes run with his spectacular 2023 season

History is written by the winners, and the abiding memory of the 2023 NFL season will always be Patrick Mahomes and the Kansas City Chiefs celebrating going back to back with a second successive Super Bowl win.

It meant a heartbreaking end to a spectacular first season as the starting quarterback for the San Francisco 49ers for Brock Purdy, who authored a remarkable campaign in which he was the MVP frontrunner for long periods, only to suffer an agonizing overtime defeat to the Chiefs.

More context that illustrates just how incredible his season was came on Tuesday, as FTN Fantasy published its failed completions data for the 2023 campaign.

A failed completion is a completed pass that fails to gain 45% of required yards on first down, 60% on second down, or 100% on third or fourth down.

Purdy's failed completion rate of 17.9% was the lowest in the NFL, but it is the other side of the coin that is even more impressive.

Indeed, Purdy had a successful completion rate (the percentage of all his passes that did gain the necessary yardage) of 57%. That was not the only the best in the league, it was the best in the league by 4.5% from Tua Tagovailoa of the Miami Dolphins.

In rocketing to the top of successful completions rankings for 2023, Purdy displaced Mahomes, who had been the top quarterback by that measure in 2021 and 2022.

As Bryan Knowles of FTN Fantasy points out, the prevalence of Shanahan offense quarterbacks near the top of the list, with C.J. Stroud in eighth and Matthew Stafford in 10th, will provide plenty of fuel to those Purdy doubters who label him as a product of his head coach's system. Jimmy Garoppolo finishing second on the same list in 2021 and 2022 could be used as further evidence for that argument.

But the case against Purdy being a true difference-maker at quarterback becomes harder to make when you trace the data all the way back to 1979, as FTN has done. In the period from that season to 2023, Purdy's campaign is the 10th best by a quarterback by successful completion percentage. Regardless of which side of the Purdy debate you occupy, it is difficult to dispute that is impressive.

In Kyle Shanahan, Purdy does have the finest offensive mind of his generation for a coach, while he is also blessed with an outstanding supporting cast. However, given the gap to the quarterbacks behind him and his place in the top 10 of a list that goes back to two seasons before the 49ers won their first Super Bowl, you would have to be the most ardent of Purdy skeptics not to credit him for such stellar numbers.

Regardless of how you apportion the praise, there's no denying the marriage of Shanahan, Purdy and the 49ers' playmakers has elevated the San Francisco offense to new heights. The frustrating thing for Purdy and the Niners is that their inability to scale those heights in the Super Bowl is the main thing people will remember from 2023.