Warwickshire 14 for 0 trail Hampshire 319 (Wheater 74, Adams 53, Rankin 6-75) by 305 runs
Fast bowler Boyd Rankin seized a career-best 6 for 75 as Warwickshire and Hampshire exchanged blows on a fascinating opening day at Edgbaston.
Hampshire were bowled out for 319, having prospered in the first session, rattled by Rankin in the second and then fought back in the third, led by a punchy 74 off 91 balls from Adam Wheater.
When the visitors, put in, reached 94 without loss, they had a solid foundation on which to build their attempt to bounce back from defeat to Sussex in their opening game of the season.
But they lost six wickets in the afternoon session, four of them to Rankin who ended with five or more wickets in an innings for only the seventh time in his first-class career.
The 30-year-old is determined to add to his one ill-fated Test appearance for England (the last match in the 2013-14 Ashes whitewash) so far. If he continues to bowl with the pace and accuracy he exhibited here, he could well force himself back into the national team.
"Of course I would love to play for England again," he said. "I thought I had a pretty good winter with the Lions in both the Test matches and the one-dayers so I was just keen to come back to Warwickshire and continue that form. "I am just concentrating on playing for Warwickshire and you never know what might happen down the line."
Rankin's work forced Hampshire into retreat and it took a bold counter-attack from Wheater to leave the match, played on a good batting pitch, evenly-poised after the first day.
At lunch, Warwickshire might have reflected they would be better off losing the first toss of the season. Last year, against Sussex, they chose to bat and before lunch were 87 all out. This time they bowled and Jimmy Adams and Liam Dawson took Hampshire to the interval at 89 without loss.
Warwickshire's attack, without the injured Chris Woakes, struggled for line early on but improved significantly, led by Rankin and Chris Wright. After Wright trapped Dawson lbw, Rankin struck twice as Adams edged to second slip and James Vince fell lbw.
Michael Carberry, a habitual plunderer of Warwickshire with a first-class average of 54.50 against them, advanced dangerously to 42 but then played on to Wright. When Rankin yorked Will Smith and had Sean Ervine caught in the cordon, six wickets had fallen for 100 runs in 33 overs.
Rankin quickly added Gareth Berg after tea but Wheater lifted Jeetan Patel for six on his way to 50 from 60 balls.
Wheater and Danny Briggs added 103 in 22 overs before the former edged the persevering Barker to first slip. Briggs became Rankin's sixth victim, lbw, leaving Warwickshire four overs batting which Varun Chopra and Ian Westwood negotiated safely, adding 14 runs before stumps.