Marcus Rashford sat out England's first training session in Russia due to a knee complaint as Gareth Southgate faced the first notable injury doubt of the World Cup build-up.
Preparations for next Monday's Group G opener against Tunisia could scarcely have gone any better up until now, with the initial 23-man selection remaining intact after beating Nigeria and Costa Rica.
Rashford shone in the latter friendly and scored a superb opener during a man-of-the-match display in last week's Elland Road send-off, underlining his claims for a starting berth when the finals get under way.
The 20-year-old's hopes suffered a setback after he missed England's first training session in Russia with a slight knee injury, but on Wednesday evening he assured fans the problem was nothing serious.
He tweeted: "Thanks for the messages I've been getting. Picked up a slight niggle but nothing to worry about #ThreeLions"
The Football Association also earlier indicated Rashford's absence was only a precautionary measure, but the Manchester United forward was conspicuous by his absence from the first session at Spartak Zelenogorsk's stadium.
England's medical staff are treating a knee issue that Southgate called a "slight knock" upon touching down in Russia on Tuesday, with midfielder Jordan Henderson using a similarly relaxed tone the following day.
"He's not too bad, I don't think," the Liverpool captain said. "It's a knock in training.
"I think we've still got five days before the first game so it's just a little bit of a precaution for him to make sure he is OK."
After training with the remaining 21 members of the squad on Wednesday, Henderson said he did not know how Rashford sustained the issue.
Eric Dier - facing a fight with Henderson to start against Tunisia - was among those involved in Zelenogorsk, but eyebrows were raised by the heavy strapping on his left thigh.
"I am fine, thank you," the Tottenham defensive midfielder said. "It is just a superstition more than anything now.
"It's just because I've had a problem with my leg and it's cleared up now.
"But I was wearing the strapping before and I just haven't stopped wearing it yet. I will eventually!"
Around 400 locals watched England's first training session, with children given Three Lions goodie bags at the start of a session that ended with the players signing autographs.
England's training ground is a 10-minute drive from their hotel in the resort of Repino, which is 29 miles north-west of St Petersburg.
The team checked in at the forRestMix Club on Tuesday evening, meaning players have yet to do anything other than rest and train.
"We just got there last night," Dier said in an interview with BBC Radio 5 Live and talkSPORT. "We were in the hotel and training this morning.
"I know over the next few days we can if we want to, so I am sure myself and others will get out and about."
And Dier is looking forward to heading into St Petersburg over the coming weeks to explore a place he has heard so much about.
"I'd like to go and see St Petersburg," the 24-year-old added. "Apparently, it is a beautiful city.
"I think it's one of the most European cities in Russia, so I am looking forward to seeing the city.
"My friend's brother used to play here at St Petersburg and he said the city was very beautiful, so it will be nice to go and see it."
Related World Cup links
- World Cup outright tips
- World Cup Golden Boot tips
- World Cup fixtures & schedule
- World Cup groups & predictions
- World Cup team profiles
- World Cup podcast
- World Cup best bets
- World Cup outsiders to follow
- Elimination predictions
- England's routes to glory
- World Cup Golden Boot contenders
- World Cup Golden Ball contenders
- World Cup Golden Glove contenders
- New world champions in Russia?
- Four £5 flutters in Russia
- World Cup venues in focus
- Full World Cup squad lists
- More free football tips
- Sky Bet's World Cup odds