Sam Robson gave the England selectors a timely reminder of his run-scoring ability as champions Middlesex took control of their Specsavers County Championship match against Yorkshire.
The opener has not featured for England since 2014 but has now scored two centuries in just four championship appearances this year to boost his slim chances of a recall against South Africa next month.
Paul Stirling posted his maiden championship century and added 187 with third-wicket partner Robson on another placid Lord's pitch.
Robson ended the opening day unbeaten on 152 to leave Middlesex well placed for their first win of the season on 337 for four.
Hampshire's former international players made important contributions to give their side the upper hand at Old Trafford.
Lancashire, who began the match six points behind third-placed Hampshire in the table, reduced the visitors to 177 for six after losing the toss but Australian George Bailey hit 127 before Kyle Abbott's late hitting left his team in charge.
Ex-South Africa bowler Abbott finished the day unbeaten on 76 from 89 balls in Hampshire's 351 for eight.
Nick Browne and Ravi Bopara posted their highest scores of the year for leaders Essex on a hard-fought first day against bottom side Warwickshire at Chelmsford.
Jeetan Patel dismissed in-form England opener Alastair Cook for 39 before Browne and Bopara moved Essex into a position of strength with a 127-run fourth-wicket stand.
Browne fell for 84 but Bopara will begin day two 16 runs short of his century with Essex 263 for five.
Samit Patel continued his stunning form as Division Two leaders Nottinghamshire took a firm grip on their match against Leicestershire at Trent Bridge.
The former England all-rounder, who followed his unbeaten 257 in his last championship outing with two important knocks in the Royal London One-Day Cup, ended the opening day on 157 not out.
Nottinghamshire will aim to bat Leicestershire out of the game when they resume on 345 for four.
Worcestershire's bowlers bounced back in impressive style from their weekend semi-final mauling in dismissing Kent for 260 on day one of their promotion battle at New Road.
But then Kent, second in the table, responded themselves with the ball despite a boundary-laced cameo from England all-rounder Moeen Ali, who made 37 off only 16 balls.
Third-placed Worcestershire, who conceded 363 in the One-Day Cup clash with Surrey, closed on 95 for three.
Glamorgan opener Nick Selman followed his match-winning century against Durham at Swansea last month with another hundred at Chester-le-Street.
But Chris Rushworth grabbed three wickets with the second new ball to finish with five for 40 as the visitors slipped from 182 for three to close the first day on 221 for seven.