London, August 19 (Reuters): Manchester United continued their perfect start to the Premier League season by crushing Swansea City 4-0 with three late goals in four minutes at the Liberty Stadium on Saturday. The scoreline matched their opening-day destruction of West Ham United after Romelu Lukaku, Paul Pogba and substitute Anthony Martial scored between the 80th and 84th minutes to add to Eric Bailly's first-half opener, his first goal for the club. Lukaku began the late rout with a neat finish on 80 minutes for his third goal in two games before Pogba surged forward to dink the ball past Lukasz Fabianski and Martial completed the destruction. Two of the goals came from assists by Henrikh Mkhitaryan, who was named man of the match. "It was a tough game, especially in the first half when they had five defenders," the Armenian said. "In the second half there was more space as they only played with four." Despite raucous home support, Swansea seldom threatened in the absence of the departed Gylfi Sigurdsson the injured Fernando Llorente, always struggling to deal with United's power and pace and by the end Jose Mourinho's side were bursting forward almost at will. "I think we are a more confident side this season," said Pogba, who gave a strong performance despite playing most of the match with a yellow card after a wild early challenge. "Last year we still won two trophies but now we all know each other better and are working for each other." His words reinforced the feeling that United are a much stronger force this season, not least because of their strength on the bench. Last week they scored two late goals to finish off West Ham and on Saturday, after injecting Martial into the attack on 75 minutes, they went one better. At Anfield, Liverpool ground out their first Premier League victory of the season after winger Sadio Mane scored an opportunistic goal to give them a 1-0 win over Crystal Palace. The pacy Mane took advantage of a double mistake by Palace midfielder Luka Milivojevic and steered the ball past Wayne Hennessey in the 73rd minute, after the Wales goalkeeper had made a string of good saves. Liverpool enjoyed the lion's share of the possession but the visitors missed the best chance of the match shortly after the break as the home side's former striker Christian Benteke blazed his shot over the bar from six yards. The opening period was a scrappy affair with passes going astray at either end. The best action came inside a minute as Hennessey denied Roberto Firmino before opposite goalkeeper Simon Mignolet kept out a fiercely struck Jason Puncheon effort. At St. Mary's, Charlie Austin scored a stoppage-time penalty as Southampton beat 10-man West Ham United 3-2 in a thrilling game in which Javier Hernandez netted his first goals for the visitors. Hernandez's double either side of halftime had seemed to complete an astonishing comeback for West Ham who trailed after Manolo Gabbiadini and a Dusan Tadic penalty put the Saints two up with their first home league goals since April. In between, West Ham's 24 million-pound ($31 million) striker Marko Arnautovic received a straight red for elbowing Jack Stephens in the face, his second dismissal against Southampton in two seasons. But West Ham refused to buckle and Mexican Hernandez thought he had done enough to earn a point before Pablo Zabaleta bundled over Maya Yoshida deep into added time and Austin converted the spot-kick. Robson-Kanu scores, gets red carded Hal Robson-Kanu grabbed a 71st-minute winner and was sent off 12 minutes later as West Bromwich Albion beat Burnley 1-0 at Turf Moor. The Wales forward bustled past Stephen Ward and James Tarkowski before firing home a low drive to give the visitors the lead. But he was shown a straight red card after his leading arm struck Burnley defender Matthew Lowton in the face as they challenged for a ball in the air. Burnley, who enjoyed a shock win at champions Chelsea in their opening game, had chances in the first half with Icelandic winger Johann Berg Gudmudsson twice going close. At the King Power Stadium, Shinji Okazaki struck early and Harry Maguire netted a header from a corner as Leicester City beat Brighton 2-0, handing the Premier League newcomers their second straight defeat. Japanese international Okazaki was on hand to rifle home the rebound from a Riyad Mahrez shot in the first minute as the 2016 Premier League champions got off to a flying start in their first home game of the season. Mahrez was also behind Leicester's second goal, swinging in a corner early in the second half for Maguire to head home his first goal for the Foxes. Brighton had plenty of possession in the second half but once again had a hard time fashioning decent goalscoring opportunities, with Leicester able to coast home. Brazilian Richarlison and substitute Etienne Capoue scored in the final 17 minutes as Watford ended a run of four Premier League draws against Bournemouth with a 2-0 victory at the Vitality stadium. In a move involving three new Watford signings, Nathaniel Chalobah broke from midfield and passed to Andre Gray who crossed low for Richarlison. His initial effort was blocked by goalkeeper Asmir Begovic but the ball ran free and the Brazilian rose off the turf to tap it home. Jermain Defoe made his second Bournemouth debut in 16 years with the score 0-0 but it was Capoue who made sure of the win for Watford with a shot from outside the box into the bottom corner in the 86th minute.