The Spaniard was removed at half-time as Chelsea entered the break three goals down against the Baggies.
However, while Mateo Kovacic made his way out to the stands for the second half after being subbed alongside Alonso, the Spaniard showered and went to the team bus outside the stadium to watch the game.
Alonso was seen back inside the stadium around the hour mark but he did not return to the stands to watch the game alongside the rest of the squad.
Lampard was furious with Alonso after the game and gave the defender a ‘dressing down’ in front of the rest of the Chelsea squad, according to the Athletic.
Chelsea showed good spirit to battle back in the Midlands to earn a point and Lampard accused Alonso of failing to show the same togetherness with his selfish decision to leave the stadium.
Alonso’s absence from the stands was particularly strange given the strict Covid-19 protocols in place across the Premier League.
Alonso has been heavily linked with an exit from the club following Ben Chilwell’s £50m arrival from Leicester and there could be movement on the defender’s future in the coming days after he angered Lampard.
Chelsea have spent upwards of £220m so far this summer and the club are keen to recoup some of that outlay by shifting some of the deadwood at the club.
The Blues will listen to offers for Ruben Loftus-Cheek, Ross Barkley, Antonio Rudiger, Olivier Giroud and Kepa.