Saracens vs. Clermont, Twickenham – Saturday, April 26

Billy Vunipola v Fritz Lee

Genuine wrecking-balls are worth their considerable weight in gold and at Twickenham, two of the most effective on the continent meet head-on. Vunipola may have been wearing six at Ravenhill om the Heineken Cup quarters, but his brawn off the back of the scrum was a key factor in Saracens scraping past an immense Ulster effort. In fact, a total of 82 carries all competition – the most by anybody – tells you all you need to know about his importance.

Not just a brute: Vunipola passes

Clermont’s pack is a mechanical, muscular beast. However, if England’s golden boy can get beyond the gainline regularly, the Top 14 giants will be thrust outside their comfort zone. Likewise, should Saracens start falling off Lee – a 17-stone Samoan with New Zealand Sevens experience and seismic power – they face a long, hard afternoon.

Alex Goode v Lee Byrne

Mike Brown deservedly wrestled every plaudit going following a phenomenal campagin. Even so, Goode remains a fine full back who is rated very highly by Stuart Lancaster. His place on the long list of the ERC European Player of the Year award is no fluke, and follows some exceptional attacking displays in the group stages. A sickening fall in Belfast robbed him of a chance to influence the quarter final, but Goode will not flinch if Brock James tests him with a few early bombs.

Preferred to the mercurial Jean-Marcellin Buttin, Byrne will be itching to prove a point and cap his final campaign in France on a successful note. Superior in the air with a monstrous boot, he also adds a bit more bulk and could easily cause havoc joining the line outside the 13 channel or off the shoulder of the superb Sitiveni Sivivatu. A far better player even than his tally of 46 Wales caps suggests, Byrne will relish another run at Twickenham.

Stand up: CJ Stander has stepped up to the mark

Toulon v Munster, Stade Velodrome – Sunday, April 27

Steffon Armitage v CJ Stander

Not a direct match-up given Armitage continues in the eight shirt, but this remains an absolutely blockbuster clash that will go a long way to deciding what could be a classic encounter. During the defeat of Toulouse, Stander allowed Thomond Park to forget about Peter O’Mahony – seriously impressive given the Munster skipper’s recent form. His captain’s shoulder operation means the former Blue Bull now has a chance to dismantle another team of stellar names from the south of France.

Stander’s destructive dynamism is superb to watch and this week Bryan Habana admitted he was a loss to the Springboks. Though almost half a foot shorter, Armitage offers even more mobility and – blessed with a big old backside and an awkwardly low centre of gravity – just as much strength. He has won 17 turnovers this tournament for a start. All over the park, not least at the breakdown, these two will tear into each other.

A safe pair of hands: Matt Giteau

Matt Giteau v James Downey

Boxing sages often say styles make fights. In rugby, contrasting approaches certainly enhance intrigue. Giteau, a canny operator from Queanbeyan who oozes class, and Downey, a downright hard-as-nails Dubliner that won a first cap at 32, are just about as different as inside centres come. And both have huge roles on Sunday.

Toulon’s former Wallaby will direct his side’s fast-paced phase-play, offering himself up as a zippy distributor and runner from first receiver. In response, Munster’s man mountain must drive rapid linespeed and marshall the mighty Mathieu Bastareaud as Leinster so glaringly failed to do. That task needs guile as well as grunt – Jonny Wilkinson and Giteau will use their behemoth midfielder as a decoy as well as a route-one cannon.

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