Chris Rogers hit the 60th first-class hundred of his career, and his second of the season, to guide Middlesex to 320-3 on the first day of the County Championship match against Sussex.
It was a tough day for top-of-the-table Sussex at Lord's against Division One's third placed side, and the only other unbeaten team in the division, with Rogers finishing on 161 not out and putting on an unbroken 123 for the fourth wicket with Neil Dexter, who is 62 not out.
Rogers and his opening partner Sam Robson had earlier put on 100 after Middlesex had been surprisingly asked to bat first by Sussex captain Ed Joyce, who clearly thought there would be some early help for his seamers on a pitch tinged with green.
Robson made a solid 54 before falling on the stroke of lunch, leg-before wicket on the back foot to 24-year-old leg-spinner Will Beer, who was playing only the third championship match of his career as a replacement for Monty Panesar, ruled out with a shoulder injury.
Rogers was fortunate to be dropped on three, by Mike Yardy going to his left at second slip as the Australian left-hander fenced at a ball angled across him by fast bowler Steve Magoffin.
And 35-year-old Rogers, who will join up with Australia's Ashes squad towards the end of this month, also had a let-off on 105, with Middlesex's total on 201, when he cut hard at Beer and saw Chris Jordan fail to cling on to an edge at slip as he dived to his left.
Otherwise, however, Rogers looked in total control as Sussex's quicker bowlers struggled to make an impact on a surface which played far better than might have been expected when Joyce made his decision to bowl at the toss.
After tea, Rogers and Dexter made sure it would be Middlesex's day and not even eight overs of the second new ball could break their excellent stand. Both Magoffin and Jordan tried hard to bring Sussex a late breakthrough, but to no avail.
In early afternoon Joe Denly laboured 51 balls for his 11, until he was bowled by a faster, skidding delivery from Beer, and Adam London, preferred to the dropped Dawid Malan, batted nicely for 18 before being adjudged lbw to Chris Nash's off spin. London did not look happy with the decision, suggesting he thought he might have hit the ball.
At the close Rogers had batted for six hours and eight minutes, facing 279 balls and hitting 18 fours, while Dexter's innings had occupied 115 balls, with seven fours.