Kyle Walker-Peters' latest muscle injury could leave Southampton with a problem at right-back once again.
The former Spurs defender trudged out of Sunday's 2-1 Premier League loss to Wolves with a hamstring problem, having only just shaken off a thigh complaint.
Walker-Peters had been able to return for Saints' 2-0 FA Cup win at Wolves on Thursday, but two games in a week took an immediate toll.
"It's not good, hamstring problems again," said Hasenhuttl.
"Two games in four days after a long injury is not an ideal thing to do.
"But we have no alternatives at the moment, so it's a pity."
Hasenhuttl made no secret of prioritising the cup having fielded a full-strength line-up at Wolves in midweek and being rewarded with a quarter-final clash against south-coast rivals Bournemouth.
The clear downside was another potentially costly injury, leaving the Austrian boss again likely to require a makeshift right-back option.
Mohammed Salisu came off the bench to replace the injured Walker-Peters on Sunday, with James Ward-Prowse slotting in at full-back.
Central defender Jack Stephens has also featured on the defensive flank.
Saints will host Chelsea on Saturday having racked up a record sixth-straight Premier League defeat, with Hasenhuttl admitting there is little option but to press forward undeterred.
Ruben Neves' hotly-contested penalty for Ryan Bertrand's handball floored Saints on Sunday, but Hasenhuttl insisted that was merely a natural response to the controversial decision.
"Six games now without a point in the Premier League; we had some good moments but in the end it's the results we have to take.
"As always we will take the time we have in the week to put the best possible side on the pitch.
"We concentrated on the cup, but until the penalty moment we had controlled everything.
"It's not so easy to keep going when you concede an equaliser like this."
Nuno Espirito Santo toasted Wolves' second league win of 2021 by calling on his wingers to threaten more in the narrow channels.
Pedro Neto's winner came from an inside-right raid, with Nuno determined his attacking players exploit those spaces more clinically.
"I think it was a beautiful goal, a beautiful action from Pedro," said Nuno.
"We can produce these moments, but the team has to keep working.
"When the wingers changed sides, when they were on the inside of the game they saw more action.
"They are very talented players, their games are based on one-v-one situations, and when they have space they are very difficult to stop."