Luckily Farah, favourite to retain his 5,000 crown and match his distance double from the 2012 London Olympics, was not required to use the blistering finishing speed that won him 10,000 gold on Sunday.
"Today it was pretty hard to get up in the morning as I am not a morning person, though I had to wake up at 6 a.m.," he told reporters.
"But we've just got to deal with it, get it out of the way and get ready for the final.
"I just wanted to do as little work as possible, freshen my legs up and get through to the final. I did that so I've just got to recover now and get ready for Friday," the 30-year-old said.
With the first five finishers in each heat guaranteed a place in the final, the Briton was happy to take his foot off the pedal, crossing the line in fifth behind Ethiopian Muktar Edris with fastest man in the world this year, Edwin Soi of Kenya in second.
Ethiopia's Hagos Gebrhiwet won the first heat despite almost taking the wrong bus from the hotel and arriving just in time for the race.
"We arrived so late that we went straight into the race without a proper warm up but luckily everything went well," he said."
Gebrhiwet was not the only athlete left bewildered at the Luzhniki with 20-km walk winner Elena Lashmanova almost making a costly mistake after slowing down in the stadium at the end of the race because she was unclear where the finish was.
"The judges didn't really explain to us that we should do one lap before the home straight and finish, that's why I stopped for a second at the stadium but I quickly understood I should keep going," said the 21-year-old who added the world title to her Olympic gold.
Aside from the hosts, the two blocks of yellow and blue clad Ukrainians in the stands had plenty to cheer about and added some much-needed atmosphere to yet another poorly attended qualifying session.
Ukraine's Ganna Melnichenko held on to her overnight heptathlon lead after season's bests in the long jump (6.49 metres) and the javelin (41.87) gave her a total of 5,619 points.
But she has only a 68-point cushion heading into a what should be a thrilling final event, the 800 metres later on Tuesday (1610).
Canada's Brianne Theisen Eaton, wife of world decathlon champion Ashton Eaton, moved up into second on 5,551 and former world junior champion Dafne Schippers of the Netherlands is third on 5,492.
Other Ukraine medal favourites Olha Saladuha, defending triple jump champion, and high jumper Bohdan Bondarenko both topped their respective qualifying rounds.
Five other medals will be decided in the evening session with Russian pole vault queen Yelena Isinbayeva likely to pull the crowds in as she goes for a third, and possibly final, world title.
(Editing by Justin Palmer)
