Neither forward has played in the NHL this season. The Sabres finish their home schedule Wednesday against the Ottawa Senators.
Nylander, 20, played four NHL games last season. Following a slow start this year, the Swede has caught fire, compiling five goals and 16 points in his last 20 outings
Overall, Nylander has scored seven goals and 26 points in 48 games.
Meanwhile, Porter, 32, has scored 16 goals and 40 points in 64 contests this season. The captain played 43 games with the Sabres over stints in 2012-13 and 2013-14.
The Sabres have today off.