The kindest thing to be said is that he is certainly not the kind of official to let a bellowing Kop make up his mind for him. Unfortunately, he really should have this time. De Santis was unresponsive on three occasions, diregarding in particular the handball with which William Gallas blocked Jamie Carragher's header in the second half.
Despite that, the home crowd could be satisfied by the maturity with which their team avoided being picked off on the break and by the manner in which they dominated the second half. "Boring, boring Chelsea," sang those fans at the end, gleefully contradicting Mourinho's pre-match assertion that it is Liverpool who "do not play with an open heart".
A goalless draw had been widely predicted and the sort of passion that might have brought a second booking for Xabi Alonso or Frank Lampard was no surprise either, but Rafael Benítez's team must have shocked Chelsea with their sustained tempo and adventure. The fierceness compensated for the scrappiness and it must have taken a while before either team could recover the calm to reflect on the significance elsewhere in Group G of Real Betis's valuable win at Anderlecht.
Minds will soon sweep on to the next clash between Liverpool and Chelsea, at Anfield in the Premiership on Sunday. By then Mourinho must come up with a way of preventing the opposition from developing the momentum that might just have rushed his team to defeat last night. Chelsea did have an impressive performer in Didier Drogba, who waged a solitary battle in attack, but it was telling that Ricardo Carvalho, called upon to defuse many attacks, was the best player on the field.
Despite all the sophisticated scheming, a match can always humble a manager. This was a meeting of the European Cup holders and the reigning Premiership champions, but a heavy disguise was standard issue. The talent of the footballers went unrecognised before the interval and the carefully prepared strategies tended to malfunction. The crowd was more likely to be exercised then by bookings than by artistry.
The sight of the refined Alonso first letting Michael Essien steal the ball from him and then, at the cost of a yellow card, snatching the Chelsea midfielder's jersey showed that even the most poised footballer could tumble into error.
Each side cared far too much about this game for the good of their composure. Chelsea did stumble across a little fluency afer 32 minutes, as Drogba shielded the ball, turned and released Arjen Robben for a run checked only by Alonso's excellent challenge. The Dutch winger was temporarily heartened and when he veered inside Sami Hyypia moments later it took a good save from José Reina to put his shot over the bar.
A goal then would have been a reward for breakaway football, though, and the gusto had largely been Liverpool's. Though each manager used a formation that can pack five footballers in midfield at a moment's notice, it was Benítez's players who were more geared to advance. They were not ashamed either to resort to the obvious.
Everyone knew that the ball would be launched for the 6ft 7in Peter Crouch and, without resorting to the panic measure of starting with the towering Robert Huth, Mourinho had no simple answer. When the Liverpool striker headed down after 19 minutes the alarmed Drogba lunged at the lurking Hyypia in the area. The Chelsea striker certainly made no contact with the ball and must have had De Santis pondering the award of a penalty. But none was given.
Chances were rare and neither Steven Gerrard nor Lampard powered the play reliably. When Hyypia accidentally chested a long ball into the path of the Chelsea midfielder after 18 minutes, Lampard skewed a drive from the edge of the area, misplacing his usual searing precision.
It ought to have been Liverpool who made the breakthrough. Luis García, soon after the interval, might have dissuaded De Santis from granting a penalty because he shook off Paulo Ferreira's pull on his arm and kept on pursuing a through-ball that was collected by Cech. Chelsea's luck held in the 56th minute when Carragher jumped for a corner and Gallas, conscious of Djibril Cissé beside him, met the Liverpool defender's header with an extended arm. The referee somehow believed the contact had been legitimate.
Three penalty appeals should have amounted to at least one spot-kick, but there were small, crucial satisfactions for Mourinho and Chelsea last night. Cech had not made a save of note and the team, reprieved by De Santis, remembered how to survive.