For the fourth year running, Atlas F1 is going to keep an eye on the battle between teammates throughout the season with a simple measurement: we compare the qualifying times of each driver against his teammate's result. After every Grand Prix, we will show how teammates have fared up against each other, and where they are overall since the beginning of the season. At the end of the season, the World Champion of Qualifying Differentials will be elected - the driver who was most beaten by his teammates, in seconds. Only those who participate in at least 15 of the 17 rounds are eligible for the coveted crown; and for those who made the efforts and participated in all 17 races, the best and worst result will be scrapped.

With fifteen qualifying sessions completed for 2001, the differentials are on a roll! Let's see which drivers deserve bragging rights.

Italy Notables

• Michael Schumacher. The German may have had an off-weekend, but the bottom line is he was outqualified by teammate Rubens Barrichello, which means that by now every single driver on the grid has been outqualified by his teammate at least once.

• Frentzen. Once again, Heinz-Harald Frentzen outqualifies his teammate by a huge gap: in Belgium, Frentzen beat Luciano Burti by 4.667 seconds (no doubt largely due to the changing track conditions). In Italy, Frentzen had a rookie teammate, Tomas Enge, whom he beat by over two seconds - already Frentzen has between these two Grands Prix alone accumulated more seconds between himself and his teammates than all other drivers in these two Grands Prix combined.

• Yoong. Alex Yoong couldn't possibly have had a tougher qualifying debut. With his own car sidelined right at the first chicane, and with teammate Fernando Alonso doing just the same to his own car, the two had to share the spare car which was set up for Alonso. Nevertheless, he managed to qualify within the 107%, not remotely far off Alonso, if you consider veteran Jean Alesi was beaten by Jarno Trulli by around about the same gap...

• The 2001 QD Champion. With only two rounds to go, the battle for the Qualifying Differentials Champion is heating up. Currently, seven drivers are still in contention - mathematically at least - for the title, but in reality only Michael Schumacher and Giancarlo Fisichella have a real shot at it.