Versatility is vital on Lions tours as players often need to play a midweek game a few days after a weekend match.
That could help Marcus Smith, who for the second match in a row helped England to narrow wins from full-back.
The Harlequin started all England’s November Tests at fly-half and despite three defeats was a constant bright spark.
However, a missed tackle on Duhan van der Merwe resulted in Scotland’s second try to put questions over his physicality in defence.
Fin Smith’s form may have hit his chances of a starting spot at fly-half, but Marcus Smith’s ability to cover two positions could give him the edge over an out-and-out 10 if he can hit top form against Italy and Wales.
Scotland full-back Blair Kinghorn, who featured at 10 regularly for his former club Edinburgh, scored a hat-trick against Italy from fly-half in the 2023 Six Nations, but now plays across the back three for Toulouse.
The 28-year-old’s passing lacked precision in the first half against England, with a forced one-handed pass hitting wing Kyle Rowe in the face.
“Kinghorn has played himself out of my team,” Warburton said. “He still goes on tour because he is versatile. I will go for Hugo Keenan as someone who is just really safe at the back.”
England wing Tommy Freeman has scored a try in all three rounds this campaign, and showed his power to crash over against Scotland from close range.
Former England wing Ugo Monye believes he is a “dark horse” to go on tour, with his ability to play centre also enhancing his chances.
“I am not sure why he is not in many Lions conversations. His error count is so low and aerially he is so brilliant,” Monye told BBC’s Rugby Union Weekly.
“He scored England’s only try against Scotland, and changed the game against France with his aerial game to get above Louis Bielle-Biarrey [for his try].”