When Pep was asked about Alexis after the game, the City boss revealed that there would have to be discussions but that was all he would give away.
There was worse news about City striker Gabriel Jesus, who hobbled off in the first half with a knee problem that will sideline the Brazilian for at least "one month, maybe two months", Guardiola said.
While the full extent of Jesus' injury was yet to be ascertained, Guardiola had suggested he could be out for "little more than a month".
It is the latest injury blow for Jesus who was forced to sit out for two months shortly after joining City previous year with a fractured metatarsal.
But not just Man City players, all the players of the league [need protecting].
"Not just the best players [need protecting], all the best players".
But Guardiola does not see Sanchez leaving Arsenal in the coming weeks.
The loss of Jesus could strengthen City's resolve to sign Arsenal forward Alexis Sanchez during the January transfer window, although Guardiola played down the possibility of a move for the Chile worldwide.
Watford is the first test, with Marco Silva's team going into the game having had nearly 24 hours extra rest than City since their defeat against Swansea on Saturday.
Guardiola also spoke about the game that ended his record with City and the performance of his goalkeeper, Ederson.
Guardiola's team have already passed many tests this season, but it is now that their endurance will be questioned.
City leads the Premier League by 14 points after 21 of 38 rounds. "But they can be out for a long time".
It is all "ifs" right now, but the chasing pack did not even have those to cling to before the Crystal Palace game.