It was at 3pm yesterday that the need to get Andrew Flintoff back in the England team became apparent to captain Michael Vaughan. England had had an excellent morning reducing South Africa to 83 for 4. Ryan Sidebottom, James Anderson and Stuart Broad had all performed well, picking up a wicket each and bowling with far greater skill and intelligence than their much-vaunted South African counterparts.
But the triumvirate were beginning to tire and the ball was losing its hardness, making it difficult for fast bowlers to force the issue on a true pitch. Ashwell Prince and AB de Villiers were capitalising on the situation, leading South Africa's temporary revival.
At this moment Vaughan would have wanted to ram home the advantage his side had created, but to achieve this goal he needed a fourth seamer; a strong, fresh body to back up the good work of Sidebottom, Anderson and Broad. But the only option he had was Paul Collingwood. The Durham medium-pacer bowled four steady overs, conceding just three runs, but batting had suddenly become a far more comfortable proposition.
There are many who feel that a bowler should make way for Flintoff in Friday's second Test at Headingley. The belief is that an extra specialist batsman is required against a good bowling attack, which South Africa still possess despite their first-innings display here.
It is not a view I hold. When a team contains a couple of crackerjack bowlers, as the Australian side of the last decade did in Shane Warne and Glenn McGrath, it can get away with playing just four bowlers. Warne and McGrath wanted to bowl for an hour and a quarter in each session and they were rarely, if ever, a liability. They gave their captain wickets and control. In such a team the fifth bowler would often bowl no more than 10 overs per day, a workload that could be placed on a Collingwood-type bowler.
But in a team containing three good but not yet exceptional seamers, as this England side does, variety and fresh legs are required. Most bowlers prefer playing in a four-man attack because they know they will get a regular bowl. When five are picked there are sessions when the ball never comes your way. At times like this you wonder why the selectors picked you.
Vaughan is a captain that enjoys having five bowlers. In the 2005 Ashes he had that number, and it allows him to tinker to his heart's content. He can walk up to a fast bowler and tell him he has got only a four-over spell and that he wants him to run in hard and bowl fast, a luxury four bowlers does not allow.
So who will make way? Unfortunately it has to be Collingwood. It is a tough call on a player who continues to give so much, more so given the poor umpiring decision that caused his dismissal on Friday.
But you wonder whether the selectors were preparing Collingwood for a fall on July 3 when they failed to confirm him as one-day captain for September's Champions Trophy in Pakistan. The selectors obviously have doubts over his ability to lead and being dropped from the Test side has the potential to reduce his standing further among the one-day side.
The batting of Broad, who scored a fine 76 in England's first innings, will make the selectors feel more comfortable about dropping a specialist batsman but the pressure on Tim Ambrose will continue to increase if he fails to perform with the bat. In the same way that Flintoff's shadow has loomed over Collingwood, the name of Matt Prior hovers over Ambrose.
Monty Panesar filled the void superbly yesterday, but he cannot be expected to do it all the time.