The 20-year-old is currently skipper of the Hammers' under-23s and been described as an 'influential captain'. Coventry moved to Lincoln on loan last January and another spell playing senior football would enhance his development. A Republic of Ireland under-21 international, he wouldn't be included in salary cap rules.
Jackett and his recruitment team will be identifying potential targets who could be prised to Fratton Park, with the funds available for one heavy-hitter in the area.
Pompey are likely to recruit a fringe midfielder from the Championship or a talented youngster in a Premier League side’s under-23s set-up.
We take a look at some players the Blues may be targeting...
The Horsham lad featured for Brighton in their 4-0 Carabao Cup win over Pompey at the start of the season. However, he's nowhere near the Seagulls' Premier League squad and has been confined to under-23s football after impressing on loan at AFC Wimbledon last term. Championship clubs were reportedly interested in the summer.
Things haven't quite worked out for the 21-year-old since his move to North End from Coventry. He's made just 10 Championship appearances - all off the bench - across one-and-a-half seasons and he'll surely want regular football to get his career back on track.
The 26-year-old joined the Rams for a reported fee of £1m in July 2018. Evans has played just one minute of football in Derby's past 15 games, however, and Wayne Rooney's side are well stocked in the engine room. The Rams may not want to loan Evans out to a Championship relegation rival so League One would be the next option.
The 21-year-old was a key player for Wycombe last season as they sealed League One promotion. Ofoborh's been around Bournemouth's squad during their Championship promotion push but has made only five appearances in all competitions. Another loan would help his development.
The former Hull captain remains a free agent after leaving the Tigers during the summer. Irvine's got plenty of Championship experience under his belt and has been keeping himself fit by training with Oldham. However, he likely wouldn't be cheap and would be short of match sharpness.
The 22-year-old's been on the fringes of Rovers' side this season, making only six appearances so far. He could benefit from a loan spell and will know Tom Naylor and Marcus Harness, having had a loan spell at Burton in 2017-18.
The 22-year-old was well regarded at Goodison Park a few years ago but his career has taken a slight dip. Nevertheless, he's a energetic, combative midfielder who is captain of the Toffees' under-23s. He was reportedly wanted by Blackpool in the summer, while Danish side Brondby have previously been interested.
The former Man Utd man has a wealth of Championship games under his belt and helped Luton to the League One title two seasons ago. Tunnicliffe's played only 10 times this season, though, and is out of contract in the summer so may want to get back playing regularly.
The 25-year-old scored two goals in 34 appearances when Wycombe were promoted last season. Freeman's only played 10 times this term, though, making only two Championship starts. He needs game time, although Wanderers may be reluctant to let him leave given their relegation battle.
Another midfielder who left Hull in the summer and is still a free agent. Stewart was reluctant to drop to League One but he may be forced to do so if unable to find a Championship club that suits.