A roll for a paper machine, in particular for a paper drying device, including an axle on whose support the roll revolves, and a surface construction connected to the axle by support members. The openness of the surface construction of the roll is higher than about 10%, preferably higher than about 20%, so that when the roll an effect is produced that sucks air inward into the roll whereby a flow of air through the roll arises. Also, a single-wire draw dryer group for a paper machine having two contact-drying cylinders and one reversing roll wherein a web to be dried is guided on support of a drying wire meandering from one drying cylinder onto the reversing roll and then onto the other drying cylinder so that on the drying cylinders, the web remains between the cylinder face and the drying wire and on the reversing cylinder, the web is situated at the side of the outside curve. The reversing roll in the dryer group is an open roll having a surface construction with an openness higher than about 10%, preferably higher than about 20%, so that the flow of air traveling along with the wire passes through the open surface construction of the roll into the interior of the roll and is discharged further out along with the wire as an air flow through the open surface construction of the roll.