'Good but not good enough' is perhaps destined to be the epitaph of David Coulthard's F1 career.

However, it has not always been his fault, as illustrated by events during the 1998 season.

The opening race in Melbourne proved to be one of the most controversial in the sport's history as DC pulled over to let team-mate Mika Hakkinen through to claim the win, thus sticking to a pre-race agreement between the two team-mates. Little did he know that the season was to follow a similar line as he proved an able back-up to his team-mate who raced to the world title.

Coulthard made his F1 start in difficult circumstances in 1994, thrust into the F1 cauldron.

He not only replaced the legendary Ayrton Senna after his fatal crash at Imola, he was racing for the dominant Williams team and was also forced to share the place with the returning Nigel Mansell through much of the season.

However, he did well when he was given the chance and was rewarded with the permanent seat for the 1995 season.

His first full F1 season was solid if not spectacular, finishing third in the drivers' championship and notching up his first GP win at Estoril.

In the off-season he moved to McLaren but even with a competitive car he struggled throughout the year. His only highlight was a second place in the famous Monaco race when only three cars finished.

But as the McLaren team gradually became more competitive so did DC, the Scot breaking the team's win drought with a first at Melbourne in 1997.

1999 was a difficult season for Coulthard, as he alternated between impressing and infuriating his fans.

At San Marino he seemed reluctant to tackle backmarkers, while at Spa (a real driver's circuit), he was magnificent. And his move on Michael Schumacher in Malaysia was one of the bravest of the season.

After surviving a plane crash at the beginning of May 2000, Coulthard seemed to have found a new lease of life, finishing second, third and first in the following three races. Despite this, his performance dropped off towards the end of the season, and he was never a realistic title contender.

2001 marked a watershed in his driving partnership with Hakkinen and for the first time Coulthard looked like stepping out of the shadow of Ron Dennis' favourite son.

Unluckily for him, though, just when he was able to deal with the challenge from his team-mate, Schumacher's Ferrari looked unbeatable.

David bought a hotel - 'The Columbus' in Monaco - and won races in Brazil and Austria, but ultimately the McLaren fell a long way short of Ferrari.

Still the Scot managed to hang onto second place in the drivers' title race with 65 points, but that's all he was doing. Hanging on.

2002 was just like 2001, only worse.

Not only were Ferrari even further ahead, McLaren were under-powered, Williams were invariably in front of them on the grid and they were unused to the Michelin tyres.

To compound those woes, team-mate Kimi Raikkonen's performances turned out to resemble those of a pre-2001 Hakkinen.

DC resisted pressure from Juan Pablo Montoya and Schumacher to score a memorable win at Monaco, one of only two non-Ferrari wins that entire season. He scored 41 points and ended up fifth, but it was a disappointing and frustrating year which saw the cool Scot enter verbal jousts with both Montoya and Eddie Irvine.

Although he began strongly in 2003, winning the opening race in Australia, his challenge fell away badly and he was forced to play second fiddle to Raikkonen.

He continued to do so in 2004, his final season as a McLaren driver.

With Montoya's arrival announced almost 18 months before his first race for McLaren, 2004 was effectively an 18-race job application for David.

However, it says everything about his underwhelming season that when it ended with him 11th in the drivers' standings, it was thought it wasn't just DC's time at McLaren but also his time in F1 that had run out.

Yet just when it appeared that the Scot's F1 career was destined to end in a whimper, it was announced that he had been given a race seat with Red Bull.

And although no race wins or podiums materialised, DC produced a highly impressive season that ended with him a surprising 12th on the drivers' table with 24 points.

Coulthard's performances saw Red Bull extend his contract and with design guru Adrian Newey having joined the team in February, hopes were high that 2006 would witness an even better year for the Scot.

Unfortunately, Red Bull's decision to focus Newey's attention on their 2007 car meant development in 2006 slowed down dramatically and then stopped altogether. And although Coulthard finished third at the Monaco Grand Prix, it was one of only five points-scoring finishes for the Scot. He ended the year with just 14 points and down in 13th place.

DC remains with Red Bull in 2007 when, hopefully, Newey's influence will - finally - pay off and the Scot can finally produce the results expected of a driver of his calibre.