A perfect 10 for England to open the defence of their World Cup crown, beating Spain with an authority expected of the only professional side in the tournament. It took 53 seconds for the gulf in class to be exposed with the first try, by full time they had added a further nine – Kay Wilson chipping in with four – and demonstrated their title credentials in the clearest possible manner.

Simon Middleton can expect far harder challenges when the competition stiffens as the tournament progresses but considering he made five changes to the side who defeated New Zealand in June, and handed 12 players a first taste of World Cup action, he can be more than content.

“It was a typical World Cup opening game, full credit to Spain, they kept coming,” the England coach said. “The score doesn’t reflect how well Spain played. In the second half we were much more patient. We developed through the game which is a good sign, 50 points, 10 tries is a great start but that’s all it is.”

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The identity of the first try-scorer will have been particularly pleasing to Middleton. Megan Jones, winning her only her fifth cap, danced her way to the tryline. Spain were caught in the headlights in the opening minutes, England determined to dazzle. Katy Mclean was imperious at fly-half, firing flat passes to her onrushing forwards, with Zoe Aldcroft and Harriet Millar-Mills cruising through gaping holes in the Spanish defence.

It took Wilson all of four minutes to score her first, going over in the left corner after a five-metre scrum. She had initially been denied by a last-ditch tackle from Barbara Plà – she was missed by Spain when she went off for a head injury assessment after 17 minutes and did not return – but there was no stopping the England wing at the second attempt.

England, at this stage, were scoring at a rate considerably quicker than the clock – 14-0 to the good after six minutes following two expert conversions by Mclean – and Spain were looking at the kind of scoreline the tournament organisers might have feared, having branded this the “most competitive ever Women’s World Cup”.

It is to Spain’s credit they repelled numerous waves of England pressure until Wilson broke the dam again – gathering a pinpoint crossfield kick and dotting down on the left. Mclean could not convert but when Wilson completed her hat-trick before half-time, the record seven tries she scored against Scotland during this year’s Six Nations appeared a feat within her grasp again.

Spain at least registered a score before half-time, kicking a loose ball ahead before working the ball wide on the right to the blindside flanker Diana Gassó after Danielle Waterman had temporarily threatened to rescue England. The fly-half Patricia García was just off target with the tricky conversion, ensuring England led 24-5 at the break.

Emily Scarratt, the star performer of the 2014 World Cup, came on for the second half and took two minutes to make her mark, ghosting over on the left for England’s fifth try.

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England’s intent to play was clear but similarly, they were the dominant force up front and Millar-Mills bulldozed her way to the try her performance warranted before Wilson ran in her fourth, again in her favoured left corner. “We’ve got three out-and-out wings with us and all three are world class,” said Middleton, in reference to Wilson, Lydia Thompson and Amy Wilson-Hardy, who is likely to come into the side against Italy on Sunday. “The key is to make sure all three are fit and if we do we’re in a good position.”

By the hour mark, Middleton had made seven replacements but the changes in personnel did little to disrupt England’s flow and Alex Matthews pounced on the loose ball after Spain failed to clear their lines for the eighth score – Scarratt, taking over the kicking duties, nailing the conversion.

The replacement hooker Amy Cokayne took England over the 50-point mark from the back of a driving lineout before Thompson rounded things off on the right, having dropped one in a similar position just moments before.

England Waterman (Scarratt, h-t); Thompson, Jones, Burford (Reed, 57), Wilson; Mclean (Mason, 52), Riley; Cornborough (Clark, 60), Kerr (Cokayne, 60), Bern (Lucas, 60), Scott (Cleall, 66), Aldcroft, Millar-Mills, Noel-Smith, Hunter (capt; Matthews, 52).

Tries Jones, Wilson 4, Scarratt, Millar-Mills, Matthews, Cokayne, Thompson. Cons Mclean 2, Scarratt.

Spain Plà; Casado, Erbina, Bravo, Echebarría (Meliz, 77); P García, Fernández de Corres (Ahís, 58); Jaurena (Macías, 62), González (capt; Rico, h-t), Vinueza (R García, 52), B García, Ribera, Gassó, Medín, Redondo (Del Pan, 52).

Try Gassó.

Attendance 3,500. Referee A Barrett (SA)