Leinster will put their 100 per cent record in the PRO12 semi-finals on the line when they face neighbours Ulster at a sold-out RDS, live on Sky Sports 3 HD. Fridays provincial derby will be Leinsters seventh semi-final appearance. They have won the previous six, while Ulster have won only once at the RDS in 12 attempts.However, Les Kisss side head to the Irish capital on the back of four successive victories, including a 30-6 drubbing of Leinster in Belfast on April 30. Four points separated the teams in the final PRO12 table and a close contest is predicted on Friday. Who will prevail? Lets look at some of the key battles which could decide this derby.Johnny Sexton v Paddy Jackson Paddy Jackson won his duel with Johnny Sexton in Belfast last month Jackson has lived in Sextons shadow at international level but got the better of his fellow fly-half during their recent encounter in Belfast, and broke away for a late interception try.The Ulsterman has raised his game another notch this season, bringing the best out of a talented backline and shouldering some of the responsibility normally placed on Ruan Pienaars shoulders. Another impressive showing in Dublin should see Jackson leapfrog Ian Madigan in the fly-half pecking order for Irelands tour of South Africa, but Sexton will be out to prove a point.The 30-year-old has forged a good understanding with Ben Teo and continues to use the wrap-around to good effect. Leinster rely heavily on Sexton to unlock opposition defences and Ulster will be in his face all night, although that is familiar territory for the seasoned international.Sexton was highly critical of Leinsters performance in Belfast last month and will be desperate to exact revenge on Friday.Ben Teo v Stuart McCloskey Ben Teo is off to Worcester this summer and international rugby with England Teo plays his final game on Irish soil for Leinster ahead of his big-money move to Worcester and he could not have asked for a tougher assignment.McCloskeys form this season earned him an Ireland debut at Twickenham during the Six Nations and he looks to have nailed down the No 12 jersey in a highly competitive Ulster backline. Stuart McCloskey made his Ireland debut during the Six Nations Both players are excellent gain-line options, McCloskey averaging 4.18 metres per carry in the PRO12, while Teo has the ability to terrorise opposition defences with his running lines and offloading ability.While Sam Burgess flopped in rugby union, fellow league convert Teo has thrived in the 15-man code. With England reportedly set to fast-track him into their squad, he and McCloskey could be facing off at international level in the near future.Isa Nacewa v Jared Payne Jared Payne was among the tryscorers when Ulster defeated Leinster in Belfast last month Nacewa moves to full-back in place of the injured Rob Kearney and offers a different attacking threat to the Irishman at 15.The Leinster skipper has enjoyed a highly impressive comeback season and Ulster know any loose kicks will be punished by the 33-year-old. Jared Payne has been making up for lost time since his return from injury Paynes defensive attributes sees him start at outside centre for Ireland but he has been in scintillating form at full-back for Ulster since his return from the foot injury that ended his World Cup. He has scored four tries in as many PRO12 games, including one against Leinster last month.Both players are fantastic counter-attackers who rarely waste possession. Payne is excellent in the air while Nacewa has a quality kicking game; they will bring out the best in the players around them.Richardt Strauss v Rory BestRory Best took over the Ireland captaincy from Paul OConnell in this years Six Nations, but rather than being buoyed by the honour, the responsibility appeared to weigh the 33-year-old down.This weekend he has a chance for redemption as he goes head to head against the man who wants his Ireland jersey, Richardt Strauss. Rory Best of Ulster Strauss has played slightly more PRO12 than Best this season - less than an hour of playing time separates them - and their lineout statistics are identical, with both boasting an 87% success rate.The statistics that separate them is at the breakdown, where Strauss 11 turnovers outweighs Best with five, and tackles, with Strauss putting in 64 hits to Bests 43. Richardt Strauss Aside from those numbers, the hookers have been making a practically even contribution on the field, but which one will make the greater impact on the day?The Ireland skipper is in no immediate threat of losing his spot in the team, but Strauss will view Fridays game as an opportunity to prove his worth to Joe Schmidt and his coaching staff who will no doubt be watching on. Also See: Sky Live: Leinster v Ulster PRO12 semi-finals on Sky Fixtures and results Rugby Union on Sky Air Max Wholesale Free Shipping . -- Stanford squashed Oregons national championship hopes again, schooling the Ducks in power football. Cheap Air Max Authentic . But what about the officials? Every sport has officials and they also have stories about hard work and sacrifice but their accomplishments are seldom recognized by anyone outside their inner circle. http://www.wholesaleairmaxauthentic.us/ . After slipping from the summit during the week, the Gunners overcame struggling Crystal Palace 2-0 on Sunday thanks to Alex Oxlade-Chamberlains second-half brace. Wholesale Nike Air Max Shoes . A knee to the thigh might have stung him the most, but his sixth straight double-double made up for the brief burst of pain. Cheap Air Max Wholesale . -- Jimmie Johnson held off a teammate, passed a pair of Hall of Famers, and dominated once more at Dover.RIO DE JANEIRO, Brazil -- Paulinho equalized late on with a volley for Brazil to draw 2-2 with England on Sunday and prevent the 2014 World Cup hosts from losing their opening match at the revamped Maracana stadium. After Fred put Brazil ahead in the 57th minute in Rio de Janeiro, Wayne Rooney teed up Alex Oxlade-Chamberlains leveler and then curled England in front with a deflected goal. But Paulinhos goal in the 82nd minute ensured England would fail to replicate its victory over Brazil at Wembley Stadium four months ago. "You want to be able to close out the game, so in that sense we are disappointed," Oxlade-Chamberlain told British broadcaster Sky Sports. "But the boys showed great passion and great fight ... its tough coming away in the heat." About 66,000 fans were in the Maracana, which has undergone renovations worth an estimated $1 billion to turn it into a 79,000-seat venue. The game was thrown into doubt last week when a judge ruled the stadium was unsafe, but the order was overturned. The confusion reflected the various cost overruns and delays in building stadiums in Brazil ahead of the Confederations Cup, which starts in two weeks as a warm-up for the 2014 World Cup. Brazils prospects of replicating its 2002 World Cup success are currently looking distant, with Luis Felipe Scolaris side having won just one of its past six games. Star Brazil forward Neymar, who heads to Barcelona after the game for his official presentation after signing a five-year deal att the Spanish champions, could find no way past goalkeeper Joe Hart.dddddddddddd Hart also denied Hulk and Filipe Luis in quick succession in the first half, and blocked a powerful shot from Oscar. "We didnt play well in the first half, but we battled and dug deep," Hart said. Brazil goalkeeper Cesar denied Theo Walcott twice in a first half dominated by the hosts. Their breakthrough came after the break when Hernanes hit the crossbar and Fred pounced from close range to stab the ball into the net. Englands fortunes turned after Oxlade-Chamberlain replaced Glen Johnson on the hour, 29 years after his father Mark Chamberlain appeared for England in the same stadium. It took just seven minutes for Oxlade-Chamberlain to score. A string of passes led to Rooney knocking the ball back for the Arsenal winger to crack a shot past Cesar. "He ripped it up ... he smashed us back into the game," Hart said of Oxlade-Chamberlain. As Roy Hodgsons side gained in confidence, Rooney took on the Brazilian defence, charged into space from the left and curled the ball into the top corner. But Paulinho made sure England failed to follow up its 2-0 win in Rio in 1984, volleying past Hart from Lucas Mouras cross. "Some draws can be labeled victories and some draws can be labeled defeats," Hodgson said. "Im a bit disappointed today, and we were playing so well in the second half I thought we might just hold on to it. But we were scotched by a wonder strike." ' ' '