James Anderson and Steven Finn both took three wickets as England had the better of the first day of the final Test against South Africa at Lord's.
Though the Proteas recovered from 54-4, Anderson struck with the second new ball to leave the tourists 262-7 at the close.
Earlier, Finn took advantage of some helpful overhead conditions and a little good fortune to run through the visitors' top order.
JP Duminy (61) and Vernon Philander (46 not out) were able to lead the fightback as batting became easier when the grey clouds parted, but Anderson returned late in the day to remove Duminy.
That wicket capped a much-needed good day for England, who require victory in order to avoid suffering their first home series defeat since 2008 and, more importantly,
losing their place at the top of the Test rankings to South Africa.
England's united front
"In striving to win this match and put the Pietersen fiasco behind them, England made it very clear today that they are united. There were huddles, team talks, hand claps and lots of back-slapping from a team that appeared to be very focused on the job in hand."
After the build-up to the Test was dominated by the
Kevin Pietersen controversy,
an England side seemingly making exaggerated efforts to appear united had one of their best days of
to put South Africa under genuine pressure for the first time this summer.
In truth, their success was down to some excellent bowling, from Anderson in particular, as well as some good luck.
Captain Andrew Strauss, becoming only the ninth Englishman to play 100 Tests, said that he was not dissatisfied at losing the toss, and he was vindicated when dark skies arrived to help his bowlers take four wickets in the morning session.
Opposite number Graeme Smith, captain for a record 94th Test, drove at a wide one from Anderson and was given out caught behind on review, before Finn took over.
The tall Middlesex paceman, preferred to Tim Bresnan on his home ground, twice benefited from reviews of gloved catches down the leg side to wicketkeeper Matt Prior.
The first, off Alviro Petersen, was straightforward, but the second, which accounted for Jacques Kallis, needed numerous television replays.
Although there was no HotSpot mark on Kallis's glove, TV umpire Rod Tucker decided that the ball had made contact, but even then there was the question of whether the hand was on the bat.
In between, Finn produced the ball of the day, nipping one down the slope to bowl Hashim Amla through the gate in what was a spell of three wickets in seven deliveries.
Needing to rebuild, South Africa were aided by rain that came at lunch, clearing the clouds and delaying play for 15 minutes.
England v South Africa
First Test, The Oval - South Africa won by an innings and 12 runs
Second Test, Headingley - Draw
Third Test, Lord's
In the afternoon sun, Jacques Rudolph and AB de Villiers were able to consolidate in a stand of 51, De Villiers looking fluent until he edged Anderson to second slip, with Alastair Cook diving low to his left to cling on to a sharp chance.
However, with Duminy coming in at seven, the depth of South Africa's batting was used to full effect as he and Rudolph combined to add 48 for the sixth wicket.
The left-handers looked untroubled until Rudolph attempted to whip the recalled Graeme Swann across the line, only succeeding in inside-edging on to his stumps, giving the England off-spinner his first Test wicket since May.
Again England came up against strong South Africa resistance, as Vernon Philander joined Duminy.
A partnership of 72 was built quickly as England awaited the arrival of the second new ball, which yielded an instant reward.
Anderson, whose efforts have been met without due reward in this series, was gifted a wicket when Duminy chased a wide one to get an under-edge through to Prior.
Further wickets before the close would have put England in total control, but they were denied in part by a power cut.
With floodlights required in the gloom, the power shortage knocked two of them out and, when a short ball struck Dale Steyn, the umpires took the players off for bad light.