A packed weekend of motorcycling sees British Superbike action return after a six-week break, the Dunlop Masters series reach the halfway mark with races 10, 11 and 12 at Mondello Park, and Quad and Sidecarcross racing reach the fifth round of their Championships at Tandragee.
With defending BSB champion Shayne Byrne a non-starter due to injury, Carrickfergus rider Glenn Irwin will lead the PBM Be Wiser Ducati team into action alongside his younger brother Andrew, who has been drafted into the team as a temporary replacement for Byrne.
Glenn is currently fifth in the BSB series, his best result being a podium at Brands Hatch in round two, and he has big boots to fill as Byrne has won eight of the last nine races at Snetterton.
He said: "This is a different experience for me with my team-mate and team leader injured, so the onus is on me to get results that the PBM Be Wiser Ducati team deserve.
"I thrive on that level of expectation, so I'm sure I can step up my performance. We had a solid test at Knockhill and got the euphoria of my North West 200 double out of the system. I'm ready for the challenge."
There is less pressure on Andrew on his Superbike debut.
He said: "I enjoyed my first day on the bike at Knockhill. It's a steep learning curve, but I'll chip away and adjust my style to the Superbike. I'm under no illusions how tough it will be, but I'll give it my best shot."
Michael Laverty and Christian Iddon will hope to turn the Tyco BMW team's fortunes around after a disappointing Oulton Park round, while Keith Farmer heads the team's Superstock 1000cc Championship bid - he is second in the series, just 11 points adrift of leader Billy McConnell.
EHA Aprilia - on a high after their Yamaha Supersport double at the North West with Alastair Seeley - have Andy Reid and Joe Collier back on Superstock duty.
Seeley has returned to his Kawasaki team, with Ballinamallard rider Josh Elliott switching to the OMG Suzuki team this weekend.
Jack Kennedy will look to extend his 14-point lead in Supersport, while Eunan McGlinchey leads the Junior Supersport (400cc) class by 29 points having won two races and taken three runner-up spots to date.
Meanwhile, after an engine blow-up prior to the last Dunlop Masters round at Mondello Park, Ballycastle rider Charles Stuart will be out to pull back lost points on Richie Ryan and Peter Moloney around the international circuit today and tomorrow.
It will be a sad occasion after the death of Martin Birrane, the owner of the Peer Group PLC and Mondello Park race track, who passed away suddenly last Saturday aged 82.
An exceptional character and a true gentleman, his death comes as plans progress to celebrate the 50th anniversary of the circuit.
Off-road, the Quads and Sidecarcross competitors return to Tandragee after a few years' absence for the fifth round of the Ulster Championship.
Reigning champion Michael McAneney heads the Quads, while Gary Moulds, with Steve Kirwin in the chair, leads the three-wheeler Championship.