Thompson’s first competitive game in charge resulted in a 3-0 home defeat to Hamble Club.
He gave a staggering 13 players their Wessex debut for Rovers, including nine of the starting XI.
The only two starters who were at the club under Shaun Wilkinson last term were striker Miles Everett and defender Fuzz Kanjanda, and the latter only appeared three times in 2021/22.
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But Thompson was in no mood to use all the new faces as a reason for his side’s dismal curtain-raiser.
‘It was awful,’ he told The News. ‘I don’t know what happened. We just never got going from the start.
‘I was confident going into the game after what I’d call a successful pre-season. But to lose 3-0 at home is unacceptable, and the players are fully aware of that.
‘There were 13 new players but I’m not going to use that as an excuse. We’ve all been together for five or six weeks.
‘It’s going to take time, we are rebuilding the squad, but I still didn’t expect us to turn in a performance like that.’
Hamble went ahead when Baffins defender Jack Francis diverted a cross past his own keeper, Dylan Kramer.
Alfie Prendergast latched onto a long ball over the Baffins backline to double the advantage before half-time.
Prendergast, who didn’t score in his nine outings for Hamble last term after joining from Totton & Eling, added his second in the second half.
‘We’d had the better chances in the first half - they had literally had just the one shot,’ rued Thompson.
‘But I’m not going to dwell on it too much, we’ve got the FA Cup tie (at home to Alton) on Friday.
‘We’ll be training tomorrow (Thursday), it might have been different had we got the three points last night but there’s no way we couldn’t do anything in between last night and Alton.
‘I’ll be shuffling things around, there will definitely be changes.’