Joe Denly hit a fine century as England impressed with the bat on day one of their warm-up match against South Africa A in Benoni.
Denly, who has passed 50 five times in 19 Test innings without a ton, struck 103 off 192 balls, with 15 fours, as the tourists closed on 337-5.
Opener Rory Burns made 56 and Ollie Pope 70 not out.
This is England’s final warm-up game before the four-Test series against South Africa begins on 26 December.
The three-day match was downgraded from its first-class status to allow England to use more than 11 players because of their touring party.
Somerset bowlers Dominic Bess and Craig Overton were on Friday to provide cover.
Denly’s century will therefore not go on his first-class record but showed the 33-year-old is in good form before the first Test in Centurion.
He played the short ball well and did not offer any chances until he was run out by Dane Piedt after a call by Pope.
“I don’t think I’ve had it quite as bad some of the boys, just a mild case of man flu I think,” said Denly.
“It was sapping heat so I was a bit tired before the end, but I’ve loaded up on medication and vitamins and I’m feeling alright.”
Opener Dom Sibley was bowled for 22 by Andile Phehlukwayo, who also removed Burns – dropped on 41 – to end the day with 2-51.
Captain Joe Root made 12 and Ben Stokes 47, having not batted in the first warm-up game this week after Year on Sunday.
Pope hit 11 fours and one six in a fluent knock as he reached the close alongside wicketkeeper Jos Buttler, who is 17 not out.
Bowlers Stuart Broad, Jofra Archer and Jack Leach did not travel for the match because of illness and England will continue to assess their condition before deciding whether they will play any part in the final two days.