The Liverpool captain was deployed in a holding midfield role for the Three Lions, who took an early lead through Harry Kane’s close-range finish.
However, Tunisia drew level from the penalty spot 10 minutes before half-time when Ferjani Sassi converted from 12 yards.
England pushed in search of regaining the lead throughout the second period – and they did so in the 91st minute when Kane glanced in the winner.
Trent Alexander-Arnold was an unused substitute for Gareth Southgate’s men in Russia.
Earlier in the day in Group G, Simon Mignolet was on the bench for Belgium as they opened up their tournament in commanding fashion with a 3-0 victory over Panama.
More Liverpool players are set for action on Tuesday, with Mohamed Salah expected to return for Egypt in their crucial encounter with tournament hosts Russia. Sadio Mane, meanwhile, is likely to start for Senegal against Poland.