Sussex 326 for 4 (Wells 102*, Nash 66) trail Gloucestershire 367 (Klinger 129*, Mustard 71, Miles 56, Magoffin 5-73) by 41 runs
There was, as Chris Jordan's bouncer hit the back of Liam Norwell's helmet, and the stem guard protecting his neck fell off, an almighty crack. Michael Klinger, at the non-striker's end, immediately felt something was awry and went to see his partner, who remained standing but shaken, while the bowler and umpires quickly offered to help, too. Out came a medic and, while Norwell was initially - and surely unwisely - deemed fit to play out an over in which he nabbed two more singles, he retired hurt at its end.
This was the incident that would shape the second day's play - and possibly the whole match - at Hove.
By the time Norwell was sconed, Craig Miles had already been bowled by the third ball of the day, from Steve Magoffin, without adding to his overnight 56, to give the lanky Queenslander his 30th wicket of the season but, curiously, his first five-wicket haul. Not long after Norwell was hit, Matt Taylor was also castled, by David Wiese. Immovable at the other end stood Klinger who turned down singles but picked off boundaries and ran hard between the wickets to finish unbeaten on 129, a mighty achievement given his side had been perilously poised at 34 for 4.
Yet it was later in the day that Norwell's absence was truly felt as Gloucestershire's bowling resources were stretched to the limit. Miles and Taylor (playing his first Championship game of the season), the two standing quicks, ran in gallantly for a pair of wickets each. But little lay beyond; Taylor's brother Jack bowled 25 tidy but toothless overs, just 11 days after having his action cleared once more, and barely uttered an appeal in anger. Benny Howell wheeled away, conceding nine no-balls and well over four an over, while Graeme van Buuren briefly left the field with a shoulder injury and managed just one over.
So "buggered" - in Klinger's words - were the seamers that, rather than taking the new ball with three overs to go, Chris Dent stayed on in search of his fifth first-class wicket. For the day's last over, Hamish Marshall's medium pacers got their first outing of the season.
Luke Wells was the main beneficiary of this, flicking and driving his way to a fourth century of the season as Sussex closed just 41 adrift of Gloucestershire's 367. The news that, having been assessed, Norwell is stable if a touch groggy, and will play no further part in the game, makes life tougher still for Gloucestershire's bowlers.
Wells reached his ton from the day's penultimate ball, his 225th, a miscued pull off Marshall flying over the slips for four. This stroke, however, was not representative of a steely innings that saw few false strokes, having begun just before lunch when Ed Joyce's attractive 25 - brimming with lovely cuts and drives - was abruptly ended as he played on to Miles.
Wells put on a healthy stand of 79 with Chris Nash, who made 66 full of attractive drives before edging to first slip trying one too many, having been struck nastily on the hand by Matt Taylor, who eventually took his wicket. Christian Davis followed soon after, spooning Taylor behind square on the leg side, then Luke Wright - looking ever so determined and bunting plenty of drives on the up - joined to put on 116. Sussex's last 70 of their fine day were put on by Wells and Wiese, who looked to push the score on as the attack flagged.
This was an unobtrusive innings, played late and full of deft deflections and neatly nudged singles. "I won't lie," said the articulate and affable Wells, "when Chris Dent came on to the short boundary I did have quite a large man on my shoulder telling me to run down the wicket and give it a slog. I knew I'd get a bad ball, and thankfully I did, albeit a streaky one over the keeper, but it was enough to get there. I'm trying to stick to what I do best, playing the ball late, each ball on his merits, all those cliches. Things are going alright."
This match's defining period awaits on Monday morning, however, when Klinger will take that new ball. "I'm chuffed to be starting again tomorrow against the new ball with three figures," said Wells. "I think the new ball might be the deciding factor of this game. If we get through that unscathed, we back ourselves to go and get a big score, 500 or something, and then it's up to us with the ball."
A win is becoming a must for Sussex, who, as Wells said, "have drawn in every way imaginable this season - from being behind and in front on first innings, weather affected, all sorts." Should they nab that elusive second win to go with their nine draws, then a late dart for promotion remains on the cards.