The South Wales club's slim ambitions of reaching the knockout phase are over following a rain-affected defeat at The Ageas Bowl
Ageas Bowl: Hampshire 97-2, Glamorgan 54-1 - Hampshire won by 21 runs (D/L/S method)
Ben McDermott smashed his fourth fifty of his Vitality Blast season against Glamorgan to put defending champions Hampshire Hawks in prime position for a quarter-final spot.
Australian McDermott pinged 54 off 27 as Hampshire scored 97 for 2 in 9.2 overs before rain descended on the Ageas Bowl and Glamorgan were set 83 in six overs.
Colin Ingram splattered a quick-fire 34 to give the Welsh side hope but John Turner's two-run over and good defensive bowling from Nathan Ellis and James Fuller meant the Hawks restricted them to 54 for 1 and won by 21 runs.
Hampshire move level with Surrey in second on 16 points to open up the possibility of a home knockout tie, with victory against Gloucestershire on Sunday confirming their progression. Glamorgan's unlikely route to the quarter-finals, which would have needed two wins and a big net run rate swing, is now ended.
James Vince had initially been the aggressor, having been asked to bat by Glamorgan, with the first legal delivery of the match carted to the straight boundary.
Glamorgan faced an uphill battle in the reduced chase (Warren Little/Getty Images)
But he fell to a steepling catch at fine leg by Prem Sisodiya in the fourth over to give Jamie McIlroy his 19th wicket of a successful campaign.
On his return from a broken foot, Tom Prest leaned back and pummelled his third delivery for six but was leg before to Peter Hatzoglou soon after.
McDermott had taken control of that 48-run stand with a pair of maximums to the longest boundary at midwicket and another over square leg.
The Hobart Hurricanes star has been overshadowed by Vince's scoring exploits but has now pilfered 371 runs at a strike rate of 144.
He reached his half-century in 23 balls as the Hawks intelligently raced to 97 for two in 9.2 overs before the persistent drizzle kept the players off for just over two hours.
Prem Sisodiya celebrates taking the catch to dismiss James Vince (Warren Little/Getty Images)
Glamorgan were given six overs, with an 11-ball powerplay, to find their way to their new target and sent overseas Ingram up to open with Kiran Carlson.
Ingram did what he was asked to do in the first over by hitting a six over long off before a pair of boundaries in a 19-over opening.
But John Turner bounced back with a superb second over which only went for two and included five dot balls.
Nathan Ellis and Benny Howell kept the visitors under the rate before the former had the dangerous Ingram caught for a 13-ball 34 with 40 needed off 10 balls.
Ellis only went for 17 in his two overs before Fuller's finale was cut three balls short as rain returned with an impossible 29 still needed.
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