Harpe had been widely expected to start but Tait has earned a recall against the team who he made his debut against five years ago. The teenage Tait suffered at the hands of Gavin Henson that afternoon and since then his international career has been a stuttering affair.
Despite excelling during the teamÃ¢â‚¬â„¢s sensational run to the 2007 World Cup final, Tait has been largely anonymous since Johnson became team manager. But he will take his place in a potentially explosive backline which also includes full-back Delon Armitage and scrum half Danny Care.
Care is another who was not expected to start but with Wales short of options in the no.9 position, Johnson has elected for CareÃ¢â‚¬â„¢s tenacity over the more slick Paul Hodgson.
Up front there are fewer surprises with the only two capped props available, Tim Payne and David Wilson, flanking hooker Dylan Hartley in a front row which can expect a stern examination from its vastly more experienced Welsh counterparts.
Wales have delayed naming their team until Lee Byrne, their instrumental full-back, has discovered the result of his appeal against a two week ban for being the sixteenth man on the field during the Ospreys v Leicester Heineken Cup match last month.
The hearing takes place in Glasgow at 5pm this evening.
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