The 29-year-old featured in four pool stage matches as the Welsh region qualified as one of three best runners-up, scoring a try in their 17-16 defeat at RC Toulon, whom they will face again in the quarter-finals at Stade Felix Mayol on April 3.

McNicholl is one of six Scarlets in the starting XV named by new head coach Wayne Pivac, who was in charge at Parc y Scarlets before taking the national team role.

Prop Wyn Jones and hooker Ken Owens fill two-thirds of the front row, while lock Jake Ball partners captain Alun Wyn Jones in the second row.

In the backs, full-back Leigh Halfpenny will make his 86th appearance for his country and centre Hadleigh Parkes occupies the No.12 jersey.

“It is great for Johnny McNicholl to get his first cap. I thought he played really well against the Barbarians, so it is a great opportunity for him this weekend,” Pivac told the Welsh Rugby Union website.

Scarlets' fellow Challenge Cup quarter-finalists, Dragons, are represented in the starting XV by flanker Aaron Wainwright, while prop Leon Brown, lock Cory Hill and back-row forward Ross Moriarty are on the replacements’ bench.

The Dragons face a trip to Ashton Gate to take on Bristol Bears in their quarter-final on April 5, live on BT Sport and beIN SPORTS.

Scarlets wing Johnny McNicholl has been rewarded for a string of impressive displays in the European Rugby Challenge Cup with his first Wales cap this weekend in their opening Six Nations Championship match against Italy at the Principality Stadium.