The summer transfer window has now begun, with rumours and speculation continuing to swirl as Chelsea eye possible reinforcements.

The Blues failed to bring in a single player during the January window, despite seeing their transfer ban cut short by FIFA, but have already been busy this summer.

Here, Sports Mole rounds up the latest news on possible comings and goings from Stamford Bridge.

Thursday morning's Chelsea transfer talk news roundup:

Kai Havertz passes Chelsea medical ahead of club-record move?

Bayer Leverkusen midfielder Kai Havertz has reportedly passed his medical for Chelsea ahead of his proposed club-record move to Stamford Bridge.

The 21-year-old is expected to put pen to paper on a five-year contract with the free-spending Premier League side after they agreed terms with Leverkusen for the in-demand playmaker.

The deal is thought to be worth an initial €80m (£71.3m), with that fee potentially rising as high as €100m (£89m) with add-ons.

German outlet Bild reports that Havertz underwent his medical in London on Sunday and Chelsea are now understood to be working on the official confirmation of the deal.

Recent reports claim that the paperwork between the two clubs has been signed for more than a week.

Frank Lampard's side have been one of the busiest in the transfer market this summer, already bringing in Hakim Ziyech, Timo Werner, Thiago Silva, Malang Sarr and Ben Chilwell ahead of the imminent arrival of Havertz.

The latter deal will surpass the £72m Chelsea paid to sign goalkeeper Kepa Arrizabalaga in 2018.

Lionel Messi 'agrees £623m deal with City Football Group'

Lionel Messi has reportedly agreed a staggering €700m (£623m) deal with City Football Group as the Argentine prepares to leave Barcelona.

The forward recently told Barca that he wants to leave the Catalan giants during this summer's transfer window, and the South American's father and agent Jorge Messi has flown to Spain for talks.

Manchester City have emerged as the favourites for the 33-year-old despite suggestions that Chelsea, Manchester United, Paris Saint-Germain and Inter Milan were also interested.

According to the Daily Record, Messi has agreed a five-year deal with the City Football Group which will see him represent City before eventually joining MLS outfit New York City FC.

The report claims that the attacker is likely to spend three seasons with the Citizens before moving to North America, although there is 'a degree of flexibility' in the deal.

Messi was not present during Barca's pre-season training session on Monday, while he also did not turn up for a coronavirus screening on Sunday as he looks for an exit.

The four-time Champions League winner has a contract at Camp Nou until next June, but he is attempting to leave on a free transfer despite a clause allowing him to depart for nothing this summer expiring in June.

More transfer news from Chelsea:

Chelsea told to pay £30m for Rennes goalkeeper Edouard Mendy?
Ligue 1 outfit Rennes reportedly tell Chelsea that it will take a bid of at least £30m to prise goalkeeper Edouard Mendy away from the club this summer. Read more.