Glamorgan 214 for 4 (Hemphrey 75, Root 53*) trail Derbyshire 378 (Reece 111, Hughes 82, Dal 64) by 164 runs
On the day it emerged he had been suspended from bowling over a suspect action, Glamorgan's Billy Root led a fightback with the bat on the second day of the Division Two match against Derbyshire at Derby.
Joe Root's younger brother arrived at the crease shortly after Glamorgan revealed he had been banned from bowling following a review of his action, and he responded with an unbeaten half-century to steer his team to 214 for 4 at the close in reply to Derbyshire's 378.
Glamorgan released a statement, saying Root had been suspended from bowling in competitive County cricket after his bowling action was reviewed under the ECB's process for Bowlers with Suspect Actions.
"Root's bowling action was subject to an independent assessment, as set out under the ECB regulations for the review of bowlers reported with suspected illegal bowling actions, on Wednesday 8 May 2019," the statement said.
"The report from the assessment was received by the ECB on Friday 17 May 2019 and concluded that Root's bowling action displayed elbow extension in excess of the permitted 15 degrees.
"Root has therefore been banned from bowling for England and in competitive county cricket from 17 May 2019 until such time he has submitted to a fresh independent assessment in which it is concluded that he has remedied his action."
The first target for the visitors was 229 to avoid following-on and Nick Selman and Hemphrey were made to work hard by accurate bowling combined with some hostility from Logan van Beek.
Derbyshire's discipline and patience was rewarded when Selman became Tony Palladino's 350th wicket for the county in all formats and although Marnus Labuschagne upper cut Rampaul for six after tea, he was lbw offering no shot in his next over.
Luis Reece was getting the ball to swing and, although David Lloyd twice drove him through the covers for four, the Glamorgan captain got a leading edge to point as he aimed to play through midwicket.
Hemphrey was showing the application required and reached his third consecutive championship 50 as he and Root dug in. Root survived a sharp chance to second slip off Hughes on 16 and he made the most of his reprieve by cover driving the all-rounder for three fours in an over on his way to a 61 ball 50. Hemphrey resisted for 259 minutes until he was lbw to a full-length ball from van Beek but Root was unbeaten on 53 at the close.
Glamorgan would have expected to keep Derbyshire below 350 after Lukas Carey, who claimed a career-best 4 for 61, struck three times with the second new ball only for Dal and Ravi Rampaul to add 50 for the last wicket.
Daniel Douthwaite claimed his second championship wicket when Matt Critchley steered him to second slip before Carey brought one back to bowl Hughes off a glove.
Logan van Beek was beaten by a full length ball and when Palladino skied a pull to deep midwicket, a fourth batting point looked unlikely at 328 for 9.
But Dal played impressively after being clattered on the helmet and three fours from a Douthwaite over took the home side to 350. Some uncomplicated blows from Rampaul added to Glamorgan's frustration. Dal was finally bowled by Michael Hogan, but he had given Derbyshire the chance to put Glamorgan under pressure if they could take early wickets.