Jeff Saturday reacts to Patrick Mahomes' six-touchdown performance against the Steelers and finding the right player in each situation. (0:41)

Any given Sunday ... every quarterback has a shot to sit atop the Total QBR leaderboard. While QBs are most often judged by wins and losses or touchdowns and interceptions, we like to rank them every week by the stat that measures their per-play contribution to their team's cause.

An explainer of QBR can be found here, but the main idea is to capture more elements of a quarterback's play than traditional methods usually consider. QBR includes the value (or lack thereof) of quarterback rushing, sacks, fumbles, relevant penalties and -- crucially -- the down and distance of every play. QBR works on a 0-to-100 scale, where 50 is roughly average and 75 is about Pro Bowl-caliber play.

Each Tuesday in this space, we'll highlight the best and worst QBR performances from the NFL weekend and break down what made each quarterback perform at either extreme.

Which quarterbacks were the best and worst of Week 2?

Top 3

Total QBR: 96.8

How do you top throwing for four touchdowns and the fourth-best Total QBR in the opening week of the season? How about tossing six touchdowns and leading the league the next week?

Mahomes' arm is for real. He was especially excellent with deep passes in Week 2, connecting for four touchdowns on throws of 15 or more yards downfield, tied for the second most in a game since 2006:

Patrick Mahomes Passes 15+ Yards Downfield Completions Attempts Yards TD INT 7 10 195 4 0

He also becomes only the third QB in the Total QBR era (2006 to present) to post a QBR of 65.0 or better in each of his first three starts, joining Colin Kaepernick and Jimmy Garoppolo. --Gargiulo

Total QBR: 95.1

Two weeks into the season, Fitzpatrick already has two games of a 95-plus Total QBR, doubling the number he had entering the season. And this week wasn't a carbon copy of Week 1, when he was aggressive downfield.

Instead, Fitzpatrick relied on throws of 10 yards or fewer downfield to do damage against the Philadelphia Eagles:

Ryan Fitzpatrick Passes Of 10 Yards Or Fewer Completions Attempts Yards TD INT 20 22 154 2 0

Fitzpatrick was especially efficient when targeting Mike Evans. He was a perfect 9-for-9 while targeting Evans on throws of 10 yards or fewer downfield, including a third-quarter touchdown that ultimately proved to be the game-winning score. It's a connection to continue watching, as Evans has caught 17 of 19 targets for 230 yards and a pair of scores this season with Fitzpatrick under center. --Gargiulo

play 1:25 Stephen A.: Stay with Fitzpatrick unless he plays 'like garbage' Stephen A. Smith says Tampa Bay shouldn't disrupt FitzMagic when Jameis Winston returns, but Max Kellerman says Winston is a constant distraction.

Total QBR: 94.5

Give the Jaguars credit: They learned their lesson. After being seemingly petrified of letting Bortles throw away an AFC championship last season (spoiler alert: Jacksonville's overly conservative playcalling threw it away anyway), the Jags leaned into Bortles and kept their foot on the pedal on Sunday after taking a lead on the New England Patriots. He threw 45 times.

And lo and behold, it worked. Bortles was able to keep the offense moving through the air and with his legs -- he ran for three third-down conversions -- and, with a little help from Keelan Cole's fingertips, was able to outduel Tom Brady. --Walder

Blake Bortles On 3rd Down Completions Attempts Yards TD Rushing 8 10 81 1 4/33

Just missed: Matt Ryan, Atlanta Falcons (94.4); Philip Rivers, Los Angeles Chargers (93.5)

Bottom 3

Total QBR: 14.9

Well, it was better than Nathan Peterman. But nonetheless, Allen -- the polarizing quarterback the Bills selected in the first round of the NFL draft -- had a rough go in his first NFL start against the Chargers.

The former Wyoming quarterback's two picks represented two separate problems. On the first, he was under pressure and appeared destined to be sacked before attempting a speculative pass that was promptly picked. Maybe more worrying, he had a clean pocket on the second one and just made a poor throw that was quite easily intercepted.

Of very small consolation, that second pick came in garbage time, so it was heavily downweighted in QBR. --Walder

Josh Allen Week 2 Pass Plot Completions Attempts Yards TD INT 18 33 245 1 2

Total QBR: 18.2

The Miami Dolphins trampled on the Darnold breakout party a week after the rookie dazzled in his NFL debut.

The former USC QB threw two picks -- his most costly plays on the day -- but his QBR was lower than most might expect because he also fumbled (he was penalized for that, even though his teammate recovered) and was sacked three times, including twice on second down. Those are plays that don't show up in traditional passer rating but were poor plays, so they counted in QBR.

Jets fans will likely chalk this one up to growing pains. And frankly, it could have been worse. The Jets fell just shy of scoring a touchdown before halftime, and they still had a shot at the end. --Walder

Sam Darnold Week 2 Pass Plot Completions Attempts Yards TD INT 25 41 334 1 2

Total QBR: 27.2

The Bears came after Russell Wilson, and the Seahawks quarterback paid for it.

The pass plot seen here doesn't do Wilson's struggles on Monday Night Football justice, because most of his problems came before he threw the ball -- though the pick-six to Prince Amukamara certainly was an issue, too. Led by Khalil Mack, the Bears sacked Wilson six times in their win over the Seahawks on Monday (QBR places some of the blame for sacks on the quarterback). Even more of a problem: Wilson fumbled on two of those six sacks.

Wilson actually had the lowest raw QBR of the week, but because he was on the road and our model respects the Bears' defense, he moved up to third-worst in Total QBR after opponent adjustments. --Walder