ESPN's rugby predictions: Game of the week, player to watch & more

All eyes will be on London and Dublin this weekend as two of rugby's biggest cathedrals play host to the Aviva Premiership and PRO14 finals. In France, meanwhile, the Top 14 has been whittled down to the final four as Montpellier, Lyon, Racing 92 and Castres chase glory.

James Harrington runs the rule over the four matches to predict which player will shine brightest, who will have an afternoon to forget and a whole lot more.

Player to watch

Tadhg Beirne (Scarlets). It's no wonder Kildare man Beirne, 26, won Scarlets' Players' Player and Supporters' Player of the Year last weekend. He has been off-the-charts outstanding for the defending PRO14 champions week-in, week-out, and heads to Dublin for his last game for the club before joining Munster on a two-year deal. When his return to Ireland was announced, just about a year after being told he was surplus to requirements at Leinster, Beirne said that he wanted to find out if he was good enough for an Ireland call-up. That question has already been answered. On Wednesday, he was named in Joe Schmidt's squad for June's tour of Australia. He's more than good enough.

Game of the weekend

Exeter vs. Saracens, Saturday, 3 p.m.

Anyone who saw the Premiership semifinals will know that these two sides each put on command performances. Saracens were sporadically brilliant and consistently destructive in their 57-33 eradication of Wasps, while the Chiefs showed Newcastle just what it takes to challenge for a title, winning 36-5 at Sandy Park. With two Premiership wins over Saracens already this season, the champions will fancy their chances of retaining the title they won after extra-time last season -- but you can bet their opponents will have plenty to say before Wayne Barnes blows the final whistle.

Potential upset

Montpellier vs. Lyon, Friday, 8 p.m.

To be honest, either one of the Top 14 semifinals could spring an upset. But the match involving Lyon, in their maiden Top 14 playoff semifinal and chasing their first title in 85 years, bears all the hallmarks of a big one. Montpellier start as favourites, having finished first in the regular season, however, Lyon effectively enjoy home advantage with both semifinals being played at a 'neutral' venue -- Olympique Lyonnais' Groupama Stadium. And Vern Cotter's side really haven't travelled well this season. Of the 81 points Montpellier amassed to finish top of the pile, 63 -- more than 75 percent of their total -- came at home. There's potentially some good news for sentimentalists, too. Fears that the retiring Freddie Michalak's career had been prematurely ended in Lyon's victory over Toulon may have been exaggerated, and he could yet make the bench on Friday.

Big weekend for...

Isa Nacewa (Leinster). The European champions are confident Nacewa will be fit for Saturday's final, despite being forced off with a leg injury at half-time in last weekend's hard-fought semifinal victory over Munster at the RDS. Whether he starts, comes off the bench, or is restricted to water-carrying duties, one thing is certain -- this is the second, very definitely final hurrah for one of Leinster's cult heroes. A second trophy of the campaign, this time in front of a vociferous Dublin crowd, would be a fitting way to crown his final season and top off a tremendous career.