I still find it mildly incredible that more readers have yet to stumble on the work of James Grayson, particularly as he’s made a very compelling case for a simple, accessible metric in Total Shots Ratio, with solid predictive power, even in the short term.

Anyway, Grayson wrote a post yesterday that should give Chelsea fans wary of Rafa Benitez pause:

During the time Benitez was in charge Liverpool’s 38-game TSR ranged from 0.613 at it’s lowest to 0.707. Values in this range are typically expected to return 73-88 points over the course of a season, whereas Liverpool took 58, 63, 68, 76, 82 and 86 – an average of 72 points. To provide some more context the Premiership Champions have an average TSR of 0.635 so in other words Benitez gave Liverpool a very good chance of winning the title at least once during his tenure. A bit of luck here or there and it could easily have happened. The team were on a stark decline in Benitez’s final season – it may have been the best time to cut ties.

The full graph offers some compelling reading. Most will note the obvious: Benitez took over Liverpool when it already had a strong team as far as performances, maintained the high standard, and then left about a season after the club’s performances began to decline. Moreover, readers and Chelsea fans will note the slight underperformance of the club against TSR, which, albeit in the meaningless short term, is also reflected in Chelsea’s last two fixtures.

Considering the statistical evidence that Di Matteo’s luck in the 38 game Premier League was always likely to run out, Roman Abramovich could have done far, far worse than picking up Rafa. There are a lot of questions still to be answered (principally involving when Liverpool’s personnel problems end and Benitez’s managerial prowess begins), but Benitez’s pedigree, at least in the Premier League (I don’t have data for his time at Inter), is impressive.