Porsche factory driver Nick Tandy will not make his British Touring Car race debut this season.
Tandy tested Motorbase's third NGTC Ford Focus at Snetterton earlier this month.
He and fellow GT driver Michael Caine helped improve the set-up on the Motorbase cars, which had their best showing of 2013 at Snetterton last weekend in the hands of Mat Jackson and Aron Smith.
There was the possibility of Tandy racing with the squad this year, but the 28-year-old's Porsche GT responsibilities, which include the European Le Mans Series, mean he has decided not to make his BTCC debut.
"I was happy to do the test, but I've got too many GT commitments to be able to put my full focus into the BTCC," said the former McLaren AUTOSPORT BRDC Award finalist, who had permission from Porsche to race the Focus.
"If I was looking for a potential career in touring cars in the near future I'd do it, but at the moment I'm not.
"I'm grateful for having the run and am pleased to help [Motorbase boss] David Bartrum when I can, but doing a one-off test is different to committing to a full race weekend."
AUTOSPORT understands that Motorbase does not yet have plans to put another driver in its third car to race alongside regulars Jackson and Smith.
Features editor Kevin Turner
The BTCC doesn't know what it's narrowly missed with Nick Tandy's decision not to race in the series.
Tandy is one of the fastest racers around, even if British audiences generally aren't aware of him yet.
It took the ex-Formula Ford and F3 racer a handful of laps to get on BTCC qualifying pace at Brands Hatch and he outpaced Jackson and Smith for much of the Snetterton test last month until car issues intervened.
He's also spectacular. Even Motorbase, which has run some pretty handy drivers over the years, was impressed with his car control.
On one lap he had the Focus sideways all the way around the high-speed Coram right-hander. And the onboard shots showed he was doing so one-handed half the time!
But most of all, Tandy is a racer. He knows how to look after himself and there is no way he would have been bullied around in the BTCC, despite its cut-and-thrust reputation.
It would have been fascinating to see him in among the likes of Jason Plato, Matt Neal and Gordon Shedden, all of whom have title challenges to worry about.
That said, Tandy's decision is probably the right one. He has been a Porsche star since he first rocked up in a Carrera Cup GB guest outing (he won) in 2008 and his factory deal is the biggest and best chance of his career so far.
Often the fastest Porsche GT driver in the myriad number of events he has already done in 2013, which have ranged from Daytona to Spa, Tandy should be a Porsche driver for many years to come. And might even get a crack at Le Mans.
That's good news for British fans, who will still get the chance to see Tandy race in British GT events this year.
But it would have been nice to see a Tandy raid on the BTCC.