Scottish Open: Felipe Aguilar & Scott Hend joint leaders at windy Castle Stuart

Chilean Felipe Aguilar and Hend both posted rounds of 69

Chilean Felipe Aguilar and Australian Scott Hend lead the Scottish Open on three under par after an opening round dominated by testing wind conditions.

Both capitalised on early tee times at Castle Stuart when the breeze was slightly less powerful.

Former major winners Graeme McDowell, Padraig Harrington and YE Yang are among eight players one shot behind.

Home favourite Russell Knox, playing a few miles from his native Inverness, is three shots adrift after an opening 72.

Fellow Scot Craig Lee responded to being three over after just two holes to finish one under par, while a trio of Englishmen - Andy Sullivan, Eddie Pepperell and Tyrrell Hatton - are among the pack one off the lead.

American Phil Mickelson, who won this tournament when it was last held at Castle Stuart in 2013, endured a frustrating afternoon, finishing seven shots off the pace on four over.

'It's goofy golf when it's this windy'

Aguilar and Hend finished almost simultaneously having teed off at the first and 10th holes respectively. They probably did not anticipate the scores they posted would not be matched despite the fierce wind they were exposed to.

"It was very difficult golf today," said Aguilar.

"The 18th usually is a hole that we can reach in two. I hit a driver, then I hit a two-iron second shot and a four-iron third shot and barely made it, just on the front of the green."

Padraig Harrington, noted for his ability in windy conditions, is handily placed a shot behind

Conditions worsened for the most part. A bogey on the last left Knox on level par but he was not too despondent at that outcome.

"Today was extremely difficult," he said. "I haven't played in too many tougher rounds to be honest. It's kind of fun. It's goofy golf when it's this windy.

"It was a guessing game. You're just pulling a club and hoping for the best. It was borderline too windy, balls were rolling on the green multiple times. It was hard."

A clutch of Scots join Knox on level par with Richie Ramsay, David Drysdale and late qualifier Jack Doherty all just three shots off the lead.

Marc Warren, who had reached two under par in his round, had to settle for one over as he began to struggle.

While Knox seemed to enjoy the test on his homecoming, Jimmy Gunn was less effective on his return to Scotland, posting a disappointing five-over round of 77, with Colin Montgomerie a further shot back as he prepares for the Open Championship at Royal Troon.

The tournament is not won on the first day but if similar conditions prevail, the winner may be the one who can cope with the elements rather than the course itself.

Analysis - BBC Scotland's Tom English

This was the day Castle Stuart took vengeance on those who saw it as something of a soft touch. Instead, amid winds that got stronger as the day got longer, it became a hard grind for the best of them.

Trooping in after five-and-a-half hours spent fighting 25-30mph winds, Russell Knox was a mixture of contentment and weariness after his level-par 72.

Home favourite Russell Knox endured a tough day but is in contention on level par

Knox is three behind the pace, but it could have been a whole lot more had he not kept himself together at the tail end of the draw and in the most difficult conditions of the day. "It felt like we were out there for about 10 hours," said Scotland's leading player and Ryder Cup hopeful.

"It was about as windy as you can play golf in. It was a long, long day. Tricky conditions. I'm going to sleep good tonight."

'Very close to being unplayable'

Knox was happy, but also frustrated. He levelled criticism at the way the par-five 18th hole was set up, a brute that played directly into the wind.

"It was a terrible set-up on that hole in my opinion. It was 600 yards (actually 607 yards) into a 30mph wind. They could have moved the tee up. I disagree with that hole. I hit three good shots and then three bad putts (for a bogey six).

"All day you had to put so much thought into every shot. You know, 140 yards into a 25mph wind plays 180 yards. We were constantly thinking and that makes it hard. It was very close to being unplayable.

"On a couple of the exposed holes the ball was moving a little bit. They could quite easily have stopped it. Our group backed off putts about 10 times. It took five and a half hours but I don't think we could have played much faster."