Buffalo Sabres defenceman Mattias Samuelsson has been listed as week to week with a lower-body injury, while Olen Zellweger has entered concussion protocol following the same pre-season game against the Columbus Blue Jackets.
Coach Lindy Ruff provided the Samuelsson update after the defender was injured while blocking a shot against Columbus. The timing leaves Buffalo facing uncertainty on its blue line before its regular-season opener at Columbus on 1 October.
Samuelsson had been skating alongside captain Rasmus Dahlin on Buffalo’s top defensive pairing. His week-to-week designation puts his availability for the opening game in doubt.
Zellweger also left the Columbus exhibition match and did not return after taking a heavy hit late in the second period, according to The Hockey Writers. The report said he needed assistance leaving the ice. Ruff said Zellweger was in concussion protocol, making the timeframe for his return uncertain.

Two expected blue-line options affected
The injuries have arrived as Buffalo move through the closing stages of training camp. Samuelsson’s place with Dahlin and Zellweger’s projected top-four role mean the club could be without two prominent defensive options at the start of the campaign.
Zellweger was acquired from Anaheim in June and had been paired with Owen Power in the Columbus game, according to The Hockey Writers. The specialist outlet reported that the pair appeared comfortable moving the puck before Zellweger’s evening ended prematurely.
Buffalo’s immediate challenge is not simply replacing minutes in one pre-season fixture. The team must continue assessing defensive combinations while monitoring two separate injury situations, one with a week-to-week label and another without a stated timetable beyond concussion protocol.
Ruff indicated that Buffalo had defensive depth available and, according to The Hockey Writers, said the club had not held conversations about seeking outside help on defence. That stance suggests the remaining camp sessions and exhibition fixtures could take on added importance for internal candidates.

The Hockey Writers identified Dennis Gilbert, Zach Metsa, Ryan Johnson and Radim Mrtka as possible depth options who could be considered if Buffalo need to adjust. Those names were presented as potential internal choices rather than confirmed replacements for Samuelsson or Zellweger.
Final pre-season games offer evaluation time
Buffalo have two pre-season games left, travelling to Detroit before hosting Pittsburgh in their final exhibition. Those matches give the coaching staff further opportunities to examine the available defensive group before selecting its opening-night roster.
The remaining schedule also provides a short period in which Samuelsson can be re-evaluated. The Hockey Writers reported that Ruff said the club would assess the defender over the next couple of weeks to establish how quickly he could return. That process means his status for Columbus remains unresolved rather than definitively ruled out.
For Zellweger, the public update is that he is in concussion protocol. Any projection about whether he will be ready for the opener would therefore go beyond the information made public by the team.
Buffalo won the exhibition 5-1, and the game included a look at the Power-Zellweger pairing before Zellweger left in the second period. The injuries could affect the final decisions on pairings and roster depth. With Samuelsson and Zellweger both sidelined, the Sabres have a compressed period to test depth, settle their defensive group and prepare for the opening trip to Columbus.