Andy Murray will miss his grandfather's funeral on Friday in order to play for Great Britain against Argentina in the Davis Cup.
Murray will face Juan Martin Del Potro in a repeat of his Olympic singles final in Rio at the semi-final in Glasgow.
Gordon Murray, the father of Andy and his brother Jamie's dad Willie, died last week and Jamie - who is not required to play until Saturday's doubles rubber - will attend the funeral instead.
Andy missed the pre-tie press conference on Thursday as he attended a family gathering instead but Jamie was present.
The world No 2 should play on all three days of the tie after the only other doubles option - Dom Inglot - was left out in favour of Kyle Edmund and Dan Evans.
The Brits - who won the Davis Cup for the for time in 79 years last November against Belgium - are bidding to reach the final once more against either France or Croatia.
Andy Murray has admitted to fatigue after a hectic summer schedule which saw him lost just one match in 34 at one stage, a run spanning more than four months.
British captain Leon Smith said: "We saw last year in the semi-final against Australia, you could see Andy was fatigued and he still found a way to do it.
"He's a very robust guy, both physically and mentally, so don't be surprised to see him do it."
Murray's Friday tie against Del Potro is unusual in the sense the big singles tie between the two top players normally takes place on the Sunday.
The Argentinian is still working his way back up the rankings after wrist problems, however, and is therefore ranked at present as his country's third-best player.
Nevertheless, the reality is he is a man on form after his run to the final in Rio and the last eight at the US Open, where he lost to the eventual winner Stan Wawrinka.
Argentina captain Daniel Orsanic has no qualms in declaring Del Potro his side's most important player and said: "Without a doubt.
"I think he's going through a very good moment. His comeback I think is good for the world of tennis so you can imagine what it means for us Argentinians."
Del Potro added: "I will try to play a different match from Rio. It's going to be really tough but I'm looking forward to (producing) the surprise."