Interestingly, like the opening game of last season against Roberto Martinez' Wigan - who are now, of course, in the Championship - Chelsea start a campaign against one of the league's more tactically distinctive sides, with Hull City boss Steve Bruce frequently favouring a 3-5-2 formation.
However, pre-season has revealed Bruce's flexibility, with Hull switching to a flat back four and a 4-3-3 that owes much to the versatility of Robbie Brady and Ahmed Elmohamady, who can play both wing-back and higher up the pitch in either formation. Therefore, if both started on Sunday, it still might not be possible to decipher what formation Bruce has elected for, especially because both a 4-3-3 and 3-5-2 feature a three-man midfield.
It was this zone Hull looked particularly light until the news this week they had secured two players from Tottenham - Tom Huddlestone on a permanent transfer and Jake Livermore on a season-long loan.
While the latter will be a useful squad option, Huddlestone will likely be in Bruce's first-team plans, especially with Stephen Quinn's hamstring injury ruling him out for the season opener. Huddlestone's long, accurate passes are a well-known quantity but he tends to struggle when placed under immediate pressure, so Mourinho will instruct his players to close him down quickly in midfield.
Bruce is keen to keep a trio in the centre mainly to accommodate Slovenian midfielder Robert Koren, who finished last season as Hull's top scorer with nine goals. Koren's knack for goals from midfield somewhat accounts for his lack of defensive ability. "He won't fit into a 4-4-2," Bruce says, which explains why Bruce is so keen to play with three midfielders.
However, Bruce also switched to 4-4-1-1 in the final game of the season against Cardiff, again illustrating his surprising tendency for tactical tinkering, which of course is at odds with his reputation as a backwards, ‘old-school' manager. It seems he has learnt from his time at Sunderland, who appeared lethargic, tired and out of ideas by the time Bruce was finally sacked (to make way for Martin O'Neill, whose own side incidentally ended up looking as lethargic, tired and out of ideas).
Bruce is keeping his cards close to his chest. "We're looking at one or two things," he said. "It's the ideal time with pre-season to have a look at what we've got and what we can go with. We predominantly played three at the back last season but there's all sorts of stuff we can play. We'll need to be adaptable."
The focus for Hull this off-season has been on strengthening a strike-force that simply struggled for goals. Danny Graham has arrived on loan from Sunderland along with Evian striker Yannick Sagbo, who likes to play high up the pitch and look to race onto balls in behind. With Sone Aluko returning from injury - he was one of Hull's brightest players before tragically missing the second half of the season with an Achilles injury - Bruce has a number of options at his disposal. Their last pre-season warm-up showed he could play Graham, Sagbo and Aluko in an interchanging, fluid front three (with Robbie Brady playing central midfield), although, with all three moving narrow, this might leave the full-backs exposed due to a lack of protection higher up the pitch.
Meanwhile, the signing of Maynor Figueroa may also prove crucial, what with his ability to play as the left-sided central defender in a back three, or as the wide defender in either a back three or back four. It is however, the first role which suits him best - at Wigan, he accounted for Jean Beausejour's attacking tendencies by sweeping out wide and covering in behind (meaning that the majority of Wigan's attacks stemmed down the left), and the feeling is that Robbie Brady may also benefit from his intelligence and awareness.
Brady is the major wildcard in Bruce's side. He can play practically any position down the left-hand side in any formation. Hull are likely to sit deep, and rely on counter-attacks and set pieces: in this regard, Brady's ability to whip balls in will be important, as Danny Graham's first goal for Hull in the last pre-season friendly against Real Betis illustrates.