The Germany forward has long been touted as a target for Liverpool, but the Blues appear to have stolen a march on their Premier League counterparts.
But what sort of a player will Chelsea be getting?
Here, we take a look at the numbers that make Werner one of the most highly regarded players in European football.
MEASURING UP TO THE PREMIER LEAGUE ELITE
At 24, Werner is poised to enter his prime years and appears to be improving at a rate of knots.
Last season, he scored 16 goals in 30 Bundesliga appearances, under-performing his Expected Goals (xG) figure of 17.6, according to Opta data.
This term, he has raced to 25 in 29 outings – a prolific return that is 5.5 in excess of his 19.5 xG.
The early return of the Bundesliga has given Werner chance to burnish his tally, with four goals in as many outings since the restart, including a hat-trick in the 5-0 demolition of Mainz.
But even in terms of goals-per-game, none of the leading Premier League marksmen are able to match the RB Leipzig star's average of 0.9 this season. Pierre-Emerick Aubameyang, Jamie Vardy and Sergio Aguero are all on 0.7.
Vardy and Aubameyang do boast better shot conversion rates – 32 and 26 per cent respectively, compared to Werner's 23 per cent, while Leicester City's former England striker also shades him 66 per cent to 65 in terms of accuracy.
Nevertheless, Werner compares incredibly well to his soon-to-be counterparts in England and his upgrade on Tammy Abraham's 0.5 goals per game for Chelsea could be a particularly significant one for Frank Lampard.
PUSHING LEWANDOWSKI IN THE BUNDESLIGA
Bayern Munich have also been noted as admirers of Werner and there would appear to be no more suitable heir to their prolific number nine Robert Lewandowski.
Since Werner's Bundesliga debut for Leipzig in August 2016, only Lewandowski (110) has scored more goals in Germany's top flight than his 75. Hoffenheim's Andrej Kramaric comes in third on 52
Indeed, across Europe's top five leagues this term, Werner's 31 goals in all competitions is better than everyone's return aside from the Poland superstar's 43.
No player's goals in the 2019-20 Bundesliga have been worth more points to their side than the 15 Werner's have bagged for Leipzig, while the trademark style of some of those strikes has certainly caught the eye.
GIVING RB LEIPZIG WINGS
Werner's pace in all attacking situations and speed on the break has become something of a calling card.
No player in Europe's top five leagues has scored more than his five from fast breaks in 2019-20. Vardy, PSG star Kylian Mbappe and Parma's Gervinho are on four.
In terms of goals following a carry – defined by Opta as a player travelling five metres or more with the ball – Werner also edges Mbappe out at the top of the standings 8-7. Lewandowski and Inter's Romelu Lukaku have six apiece.
Along with Leipzig team-mate Christopher Nkunku, Borussia Dortmund's Thorgan Hazard, Lazio's Luis Alberto and Riyad Mahrez at Manchester City, Werner has six assists following a carry, with that quintet only bettered by Dortmund winger – and another widely rumoured Premier League target – Jadon Sancho (eight).
Werner's overall goal involvements following a carry come to 14, putting Sancho into second place on the continent with 12. Mahrez and Mbappe are in esteemed company on nine with Lionel Messi and Sadio Mane – a man who can perhaps now breathe a little easier over his starting place at Anfield.
Additionally, Werner has got into the best shooting positions from take-ons in the top five leagues, amassing an xG of 3.1 in those situations. Vardy is the next best on 2.6.
