Since leaving the Blues, both players have forged impressive careers while winning promotion to League One with the Trotters last season.
And the pair will return to Fratton Park on Saturday as Ian Evatt’s side seek their first league victory since October 2.
Doyle netted twice in 12 Pompey appearances after arriving in January 2017 to bolster a side which claimed the League Two title under Paul Cook.
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And despite having registering just four times this season, Bolton News’ sports reporter Dan Barnes believes he’ll rediscover that scoring touch soon.
Barnes said: ‘Last season was very successful for Eoin Doyle as he was the top-scorer as Bolton were promoted back to League One.
‘To be honest, it’s not really clicking for him this season – he’s got two goals from open play. I think sometimes in Bolton’s system with just a lone striker, he can get a little isolated, especially against teams who kind of sit back.
‘It’s been frustrating for him and I think he just needs that goal to kick-start his season, but in the last few years he’s been very prolific and we (at the Bolton News) ran a piece looking at him actually being one of the most prolific scorers across the top four leagues in England since 2013.’
The case of Southampton academy product Isgrove’s time at the club is a curious one.
Many wouldn’t have envisioned the success he’d enjoy after an anonymous spell at Fratton Park following his signing in January 2019.
His involvement numbered no appearances – and three unused substitute outings against Doncaster, Scunthorpe, and Shrewsbury.
Since then, alongside Doyle, he has played instrumental roles in promotions to League One with Swindon and now Bolton.
Barnes added: ‘Isgrove is quite a popular player with the Bolton fans, he’s very hard working off the ball but also has a lot of quality in terms of that final ball.
‘It’s quite an interesting time for him at the minute because he slotted in at right-back in the last game.
‘Evatt has said that he believes Isgrove has the attributes to be a successful right-back and is open to the idea of playing him there consistently if that’s what’s needed in the team.
‘Earlier in the season he found himself slightly out of the team because Evatt has opted to go with Amadou Bakayoko on the right flank instead, but he’s one of those players who will always give 100 percent.
‘The Bolton fans recognise that and respect it.’
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