Glamorgan openers Jacques Rudolph and Will Bragg made hay in the Bristol sunshine as the Championship match with Gloucestershire headed for a high-scoring draw on the second day.
After the hosts had been bowled out for 391 from an overnight 308-5, Rudolph and Bragg put together a stand of 151 in 41.3 overs on a frustratingly bland pitch before Bragg fell for 67.
Rudolph went on to end the day unbeaten on 108, having reached his second century in successive Championship games off 152 balls, with 15 fours and a six. At 209-2, Glamorgan look well placed to at least avoid defeat.
Earlier, Michael Hogan had finished with 4-57 from 27 overs of wholehearted pace bowling, which helped restrict Gloucestershire to three batting points. Benny Howell's 47 was the only sizable contribution from their late order.
Gloucestershire skipper Hamish Marshall said: "We feel it is one of those pitches where the best time to bat is the first couple of days. If the weather stays the same, we hope some deterioration will kick in."
Former England Under-19 batsman Daniel Bell-Drummond notched a maiden County Championship century on day one at Canterbury to give Kent the edge against Derbyshire.
Bell-Drummond, 20, marked his 30th first-class appearance with a patient hundred scored in a shade over five-and-a-half hours and with only 11 boundaries as Kent posted two batting bonus points as they reached 259-8 at stumps after winning the toss and choosing to bat first on a tinder-dry pitch.
The young right-hander fell for 101 late in the day, caught on the crease and palpably leg before, to become the last of Tony Palladino's deserved haul for 5-54 for the visitors.
No one on the ground was more delighted for Bell-Drummond than Kent team-mate and former West Indies Test batsman Brendan Nash who had batted 45 minutes with the former Millfield School starlet earlier in the day.
Nash, who was born and raised in Australia, invited Bell-Drummond to Queensland during the close season and believes his stint playing Grade cricket for Northern Suburbs helped lay the foundations for a consistent second full season in the Kent team.
"Deebs came with me to Brisbane, played decent local cricket on good pitches and found out a lot about himself, both personally and as a cricketer," said Nash.
"He didn't have a coach hanging over him every day and had to fend for himself more than he had previously and I think that's really helped with his development and character building.
"He's been pretty consistent this season and county sides are giving him a lot more chirp because of that, but it's water off a duck's back to him now. I couldn't be happier for him."
Aggressive half-centuries from Jason Roy and Hashim Amla helped Surrey into a position of strength at 325-7 on day one against Leicestershire at the Kia Oval.
But Leicestershire fought hard in the field, led by Rob Taylor's three wickets for 52 runs with his bustling left-arm seam - and it was only an unbroken eighth wicket stand of 82 between Gary Wilson and Chris Tremlett which ensured the day's honours went to Surrey.
Both Wilson and Tremlett ended up on 44 not out after Amla and Roy had been joined in stands of 63 and 77 by Vikram Solanki, who also batted well for his 54.
Roy said: "It is a big frustration that three of us got past 50 today but didn't kick on to a 100.
"But the stand at the end of the day has got us up to a decent total. If we can kick on a bit more tomorrow and then bowl well, we should still have a good chance to put them under pressure. I'm feeling good at the crease at the moment."
Taylor said: "Overall I'd say it is still pretty even, although it is a shame we couldn't break the eighth wicket partnership in the final hour.
"There was a little bit in it before lunch but the pitch flattened out as the day went on, and in the conditions and with a shortboundary on one side we are pretty happy.
"Getting Hashim Amla out has to be a highlight of the day for me - if he'd stayed in for another hour he would have had a hundred and more, so it was a very important wicket to get."