The 26-year-old defensive midfielder joined the Championship outfit from PEC Zwolle in the summer of 2020 and he has established himself as a key player for Coventry.
Last season, Hamer featured 44 times for the Sky Blues, scoring eleven goals while assisting ten and helped them reach the Championship playoff final.
In the ongoing transfer window, the midfielder is attracting interest from Leeds United and Sheffield United.
Hamer has one year left on his contract, but that is not causing Coventry to drop the price.
Leeds boss Daniel Farke wants to strengthen their midfield and the Whites are keen on adding him.
However, it has been claimed that Coventry are holding out for a high price in order to let the Dutchman go.
Sheffield United are short in their midfield, with Sander Berge set to join Burnley this summer and Paul Heckibottom wants to bolster his midfield with Hamer.
Now it remains to be seen whether either Sheffield United or Leeds will come up with a bid to convince the Sky Blues to sell the midfielder.
