England’s Sam Burgess will be back from injury earlier than originally anticipated. The forward was helped from the field with knee medial ligament damage 35 minutes into their 18-4 defeat by Australia in their opening World Cup match in Melbourne on Friday.

The England coach, Wayne Bennett, said he expected Burgess to be sidelined for three or four weeks but a spokesman said on Saturday: “Following a further review of the injury, England medical staff and specialists can confirm Burgess will be back in the playing squad earlier than anticipated.”

England’s man of the match, Jermaine McGillvary, berated himself after his side’s opening loss. The Huddersfield winger was among the shining lights in an encouraging performance by England, who were in the game until the last five minutes when an eight-point scoring burst gave their hosts a flattering margin of victory.

McGillvary had given England a fourth-minute lead with his fifth try in six appearances and also caught the eye with a series of strong and mazy runs out of defence but he was critical of his own performance.

“It was decent,” he said. “The first half was alright from me but I got a bit lazy in the second half. I wasn’t happy and it’s something for me to work on, on a personal front. I could have helped my team out a lot more.”

Two tries in eight minutes from Matt Gillett and Billy Slater edged the Kangaroos into a 10-4 half-time lead but they could never fully shake off a gritty England side that refused to buckle even when Burgess went off.

“That shows the character of the team,” McGillvary said. “One of the biggest icons in rugby league goes off after 30 minutes but we still dug deep and worked really hard for each other. That shows where we’re going as a team.”

Wales endured a nightmare afternoon in Port Moresby on Saturday as Papua New Guinea ran in 10 tries to open their World Cup campaign with a thumping 50-6 win in front of a capacity crowd. John Kear’s pre-match message would have been to stay in the game to quieten the fanatical home crowd but they were simply overpowered.

David Mead helped himself to a hat-trick while Rhyse Martin added two tries and Nene MacDonald, Kato Ottio, Wellington Albert, Justin Olam and Paul Aiton each scored once as PNG showed no mercy.

Regan Grace touched down after the full-time hooter to get Wales on the board but they already have it all to do to progress to the quarter-finals with only the top side from Group C qualifying.

Kear admitted his side were schooled by their opponents. “I didn’t think we performed well in any aspect. It’s been a very harsh lesson that the southern hemisphere fellas really do carry the ball very aggressively and if you don’t stand up to that you end up getting rolled and losing field position. We just never got any opportunity to attack because we couldn’t prevent the roll-on from Papua.”

Bradley Takairangi, Isaac Liu and Nelson Asofa-Solomona scored tries on their debuts as New Zealand made an impressive start to their campaign with a 38-8 victory over Samoa at Mount Smart Stadium in Auckland.

The Kiwis have endured a difficult buildup to the tournament with the walkout of Jason Taumalolo, which followed the axing of Jesse Bromwich and Kevin Proctor, but they put their troubles behind them to celebrate their first home Test for three years in fine style.

The only disappointment was the loss of the centre Gerard Beale with a broken leg.

Jarryd Hayne drew level with Bob Fulton as the most prolific try-scorer in World Cup history as Fiji routed the United States, coached by Leeds’s Brian McDermott, 58-12 in Townsville.

A member of the Australia team that lifted the cup at Old Trafford in 2013, Hayne marked his return to the Batis with one of their 11 tries that took his total to 13. The Fijians were always in control, scoring four tries in the first 14 minutes on their way to a 36-6 half-time lead.