Colin Montgomerie continued his remorseless march to a seventh successive Order of Merit title in the weather-delayed Linde German Masters in Cologne.

Montgomerie, European number one for the past six years, carded a superb error-free second-round 67 in wind and rain at Gut Larchenhof to lie just three off the lead held by veteran Spaniard Jose Rivero.

Rivero (44) who played in two winning Ryder Cup teams, fired a brilliant 66 to storm to the top of the leaderboard at 10-under-par, one ahead of Wales' Mark Mouland, who was unable to finish his round before fading light brought a premature end to play.

Twenty nine players in the 111-strong field failed to complete the second round due to the knock-on effect of Thursday's washout and will have to return this morning.

Ireland's Padraig Harrington is six shots off the pace after carding a second successive two-under-par 70. Paul McGinley, who opened with a level par 72, added a two-over-par 74 yesterday for a halfway total of 146, the same mark as Philip Walton, who shot second one-over-par 73. Meanwhile, double US Open champion Ernie Els was disqualified after he picked up his ball on the last after finding water from the tee.

Montgomerie was delighted with his effort in the defence of his title, knowing the £208,000 first prize would give him a huge advantage over his nearest rivals in the race to be Europe's number one at the end of the season.

"I'm very tired obviously but I'm very happy with no bogeys in two days," the 36-year-old Scot said.

Rivero finished the day at 10 under with Mouland a shot behind and Retief Goosen a shot further back on eight under.

Goosen warmed up for South Africa's Dunhill Cup defence at St Andrews next week in style, adding a 69 to his opening 68.

"The last two days have been good practice for next week!" French Open winner Goosen said.

Sergio Garcia and Montgomerie were next on the leaderboard at seven under followed closely by a weary Jose Maria Olazabal and last year's runner-up Vijay Singh.

"It's very tough in the morning when you have to wake up and the body says to stay in bed!" Masters champion Olazabal said after adding a 71 to his opening 67.

"It's tough but at the same time it's a more relaxed week and you know you might not be 100 per cent - but you just try to play the best you can.

"It's been a very strange year. I'm very pleased that I managed to win the Masters. That will make it very special whatever else happens but I didn't expect to play the way I did since then.

"Here and there I had a few good rounds but overall I haven't been pleased with the way I played. I haven't been hitting the driver well for a while.

"Driving is very important, when you look at the top players in the world you have to be good off the tee to compete with them."