Eden Hazard left Stamford Bridge on Wednesday night wearing a faintly dissatisfied expression. For one thing, Chelsea had just thrown away a 2-0 lead against Roma in the Champions League to draw 3-3. Only Hazard’s late header had salvaged a point. “It’s just a draw, so we are not happy,” he said. “We just want to move on, try to forget this game.”

For another, Hazard had been substituted by Antonio Conte in the 80th minute, with a view to Saturday’s game against Watford. Hazard is still finding his way back to full fitness after missing three months in the summer with a broken ankle. Still, he looked none too impressed with the decision.

“I know that sometimes it’s important for players to rest, to be on the bench,” he said. “But me, personally, I just want to play. I missed three months of football. I just want to be on the pitch.” Quickly, however, he glimpsed the potential for a mischievous headline, and rowed back. “But the manager made his own decision, so we are happy with that,” he added.

Perhaps Hazard’s frustration was borne of the fact that he was having a superb night. In his 80 minutes, he scored two goals, created five chances, and was probably the difference between a draw and an ignominious defeat. Taken in tandem with his sensational return to the starting XI in last month's 2-1 win at Atletico Madrid, and one senses that this season Hazard is determined to impose himself on a competition that has rarely seen the best of him.

Thing is, sandwiched in between those two excellent performances were two rather more mixed displays. Against Manchester City he was subdued, starved of space and possession, outshone by his international team-mate Kevin de Bruyne. Against Crystal Palace he disappeared for long periods, drifting all over in search of the ball but without any of his usual sharpness or cutting edge.

Chelsea lost both games, which rather underlines the paradox of Hazard, a man whose brilliance has helped them to two league titles in three seasons. Are Chelsea good when Hazard is good? Or is Hazard good when Chelsea are good? Is he the talisman keeping their rickety season afloat? Or should he be doing more to drag them up the table?

Hazard, to be fair, warned us in advance about his inconsistency, coming off a long injury lay-off with little to no pre-season. “I will miss some games, I will play bad for some games,” he said on his return, which is fair enough. Equally, though, it is impossible to ignore the fact that inconsistency has been the rule rather the exception of Hazard’s career.

Eden Hazard celebrates his second goal for Chelsea (Getty)

His two goals against Roma were his first for Chelsea in nine games stretching back five months. Then there was the time he went 11 months without a Premier League goal between 2015 and 2016. For a player who occasionally bears comparison with the modern greats of the game, Hazard is a player who goes through some extraordinary cold streaks.

The technical details of his game - the turn of pace, the close control, the spatial awareness - are sound enough to suggest that this is a psychological rather than a physical issue. As proven under Jose Mourinho and now under Conte, Hazard is a confidence player, one whose apparent nonchalance perhaps masks a more complex relationship with his own emotions.

Eden Hazard scores Chelsea's second goal of the night against Roma (Getty Images)

“It’s about him saying ‘today, I have to be decisive’,” Mourinho once said of him. “When he says, ‘I’m not one of the five top players in the world’, he can be. But he cannot be in a match where he doesn’t do something in the 90 minutes that makes him decisive.”

Hazard and Mourinho enjoyed a complex relationship that reached its apex in the 2014-15 title-winning season, and came crashing down to earth shortly afterwards. But what is interesting is how, three years after Mourinho urged Hazard to be more “decisive”, Conte now cajoles him in similar terms.

“Sometimes, if Eden scores one goal, he’s happy,” Conte said after the Atletico game. “And then, if there is another situation, he prefers to make an assist rather than scoring twice. I see with Ronaldo that if he scores once, he wants two, three, four. It’s the same for Messi. So, yes, Eden can improve. It’s not about being selfish. But I like to repeat to him: in every game he must be decisive.”

For his part, Hazard insisted that he and the team were both performing at a similar level to last season. “Like I say, I missed football because of the injury,” he said. “Now I try to keep this level every game. I think it’s different this season because we play Champions League. Last year it was more easy to play every game every week. We were more fresh.

“Now it’s a little bit different, but we need to adapt the situation. But I think we are in the same level as last year. Manchester City and Manchester United are stronger than last year also. We are ready. We know the Premier League is long, so we will take time to be back.”