If Philander was pretty easy to pinpoint as the fielding team's most unsafe and consistent bowling customer, England's progress to 171 for four (only 59 overs were possible) also sported a lopsided reliance on one figure, their seasoned opener and former captain Alastair Cook.
Cook's performance was the antithesis of England's collective batting approach in the second Test, which drew stinging criticism from a host of ex-captains, and was welcomed by global rookie Westley.
England have named three Test debutants in their side with Tom Westley batting at No.3, in place of the injured Gary Ballance, and Dawid Malan coming in at No.5.
Keaton Jennings was all at sea before his third over dismissal for a duck in a repeat of his horror showing in the first innings at Trent Bridge.
England had been criticised by several former captains for some slap-dash batting in a huge 340-run defeat by in the second Test at Trent Bridge that saw the Proteas level this four-match series at 1-1.
Perhaps England's top-order troubles, himself and Root aside, also make Cook even more determined to plunder runs - and are also a reason Root is not operating at three.
The Durham star added: "But looking back if we had batted out those two days with all those overs we would have won the game".
The miserly Philander posed the greatest threat, conceding no runs from his first 23 deliveries and precious few thereafter either.
The identity of the Essex batsman's opening partner for the Ashes remains as unclear as ever following the first day of this Test.
Shortly after the break Chris Morris extracted the breakthrough as Westley (25) chased after a ball from Chris Morris that he need not have played at.
Philander took two wickets for 17 runs in 12 overs in between bouts of what was said to be stomach illness on Thursday's rain-marred first day. Bairstow scored 36 in 52 balls.
But fellow left-handed batsman Stokes, who made a Test-best 258 against South Africa at Cape Town a year ago, dismissively pulled Morkel for four. South Africa learned an very bad lot of good lessons between Lord's and Trent Bridge; maybe we didn't learn quite as quickly. When Maharaj appeared early on Westley produced the shot of the day, stepping across to whip through midwicket - the sort of shot you play with an umbrella in the mirror while imagining it's your Test debut on a crunch day at The Oval with clouds gathering and men around the bat.
A delivery that straightened and struck Cook high on the pad drew an appeal, a wider one baited Cook into going fishing but the ball fell before it reached backward point. He said: "We've a settled dressing room that is desperate to get better, and knows we're a better side than we showed last week. I felt good at the crease - and then getting out just after lunch was bitterly disappointing, especially after working so hard with Cookie to put that 50 partnership on".
"But Cookie being Cookie, he fought through that - and it's one of his best qualities".