"Frank's done a better job, I have to say", Keane told Sky Sports.
Werner, who has started training in west London but can not play for his new club until 2020-21, was linked with a host of top sides in Europe before Chelsea moved swiftly to secure his signature.
Grant has praised current Blues boss Frank Lampard for guiding the club to the final UEFA Champions League qualification position this season, qualifying his support by adding that Russian owner Abramovich would have exiled him for finishing in the same position during his tenure.
Christian Pulisic has declared himself to be "100 per cent fit" ahead of Chelsea's FA Cup final date with Arsenal on Saturday.
In his last season with Leipzig, Werner scored 34 goals in 45 games, and the 24-year-old was adamant that he will be able to continue his deadly form and adapt quickly to the challenges of the Premier League.
This year's final will kick off at 17:30 BST on Saturday with live coverage on BBC One, BBC iPlayer, BBC Radio 5 live and BBC Sport website.
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However, these are transmitted by consuming contaminated food and water and can cause significant outbreaks. It is spread through contaminated blood, intravenous drug abuse and sexual contact with an infected person.
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Yes, he is going to be expecting (soon) a giant contract extension, and the draft pick price was steep. Fitzpatrick became and All-Pro and one of the best safeties in the NFL.
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Isothermal testing: This is a biochemical testing method that enables the detection of the virus in a saliva sample. One of the them is a new Covid test that uses polyamino acids to produce a result in 30 minutes, Gold explained.
The Brazilian's deal with the Blues concludes after their Champions League campaign and he appears set to leave the club thereafter.
"Obviously there's no fans there, but everybody spoke about Emi and how good he is, but I didn't realise how good he was because I didn't see enough of him".
"In my team at Chelsea there was a lot of leaders".
But there were many pundits who doubted whether Lampard was the right man to get Chelsea back on track following the turbulent reign of Maurizio Sarri.
Whilst Werner understands the demands of the English top rated flight, he also believes his characteristics are suited to the Leading League.
"He is familiar with me now a very little bit far better and it matches pretty superior between us".
"The style of the Premier League is very fast and my speciality is that I am really fast so I think it is flawless for me to play here", he added.