Rarely can a 2-0 victory have been this comprehensive. Chelsea found this so easy, they took the opportunity for an extended rest from midway through the first half. 2-0? It could, perhaps should, have been 10.
"I'm always annoyed," said Jose Mourinho, who, during much of the second half, had looked furious at his side's inability to add to early goals.
"Sometimes I have to realise there are reasons for things. The players know they have a marathon of matches, so the intensity went down. The points were never at risk."
And that was always his objective: security at the top of the table. So, never mind a Champions League tie coming up on Tuesday, Mourinho went with his best line-up. There was no rotation, no rest for the leaders. You could see why. Familiarity is breeding content around Stamford Bridge. Settled, solid, comfortable, his first choice is a team with no evident weakness.
So smooth, so easy, so far in the ascendancy were Chelsea, by half- time, after playing what Mourinho described as "beautiful" football, the only surprise was they had not accumulated a cricket score. With Nemanja Matic and Cesc Fabregas controlling midfield, with Diego Costa a constant threat, they looked as if they could win at will. It is the characteristic of champions. The first goal was inevitably scored by Costa. He had already drawn a fine save from Ben Foster, when, on 11 minutes, Oscar arced a beautiful cross in behind the defence in his direction. As Joleon Lescott and Craig Dawson forlornly looked for an offside flag, Costa strode on. Controlling the ball perfectly on his chest, he stroked the ball home.
Fourteen minutes later, after two more astonishing saves from the visiting keeper, Chelsea won a corner. Eden Hazard received the ball on the edge of the box, advanced unchecked round Craig Gardner and slipped a left-foot shot under Foster. Unmoved, unsurprised, Mourinho celebrated by writing something in his pad; a tweak, no doubt, to perfection. A landslide looked inevitable. Especially when, on the half-hour, Claudio Yacob was sent off for a challenge on Costa that West Brom manager Alan Irvine admitted was sufficiently reckless to invite a red card. The visitors were finding it hard enough to contain Chelsea with 11 men. With 10, there was no route back.
By now, Irvine was reduced to standing on the edge of his technical area, forlornly shouting out names. Apparently befuddled by the speed and movement of their opponents, none of his players appeared anxious to acknowledge him.
"The first half I think was brilliant, another dimension," said Mourinho. "So fast, so fluid. We scored two goals, should have scored much more than that. The second half obviously was different."
He was right there. As the visitors retreated into a 4-5-0 formation, Chelsea found their every route blocked. One minute Hazard, Oscar and Willian were trying to pick their way through with multiple passing moves, the next someone was hoisting a ball over the top for one of their fliers to chase. None of it, however, was producing the expected torrent of goals.
There was a reason for that: behind his resolute defence, well marshalled by Lescott, Foster was utterly magnificent. His save on half-time, flicking the ball off Cesar Azpilicueta's toes or his reflex stop from John Terry's header early in the second or his save at Hazard's feet in the 72nd minute were the very models of defiance.
It was not quite the same at the other end of the pitch. Thibaut Courtois did not touch the ball for more than half an hour in the second half. Chelsea's two centre-backs, with the freedom of the Bridge to exploit, had endless opportunity to try to prompt forward momentum.
It was not enough. As the Chelsea attack began to lose the will to break through, all around the interest petered out. For the home crowd, attention was directed into trying to demonstrate to their manager that they could produce a supportive atmosphere.
Sunday Indo Sport