Chelsea's Christian Pulisic says he was 'dumbfounded' by Thomas Tuchel's decision to bench him vs. Real Madrid

United States star Christian Pulisic has criticized his former Chelsea manager Thomas Tuchel, saying he was left "dumbfounded and very disappointed" by the decision not to start him in the Champions League semifinal second leg against Real Madrid in 2021.

Pulisic started and scored Chelsea's goal in a 1-1 draw in the first leg in Madrid. However, he began on the substitute's bench for the return leg at Stamford Bridge despite, according to Pulisic, being assured he would be in the starting lineup.

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"What happened before that game was hugely disappointing for me," Pulisic wrote in his upcoming book "Christian Pulisic: My Journey So Far," according to an excerpt published on Tuesday.

"l'd had a really good first leg performance and our following match was against Fulham in the league. Tuchel told me that he was resting me for the second leg and as a result I didn't play a single minute in the Fulham game.

"Then on match day of the second semi, Tuchel tells me he's changed his mind and he's going with Kai [Havertz]. I honestly was dumbfounded and very disappointed. I thought that I'd earned a start and, most importantly, he had assured me previously I was going to start."

Despite previously working under him at Borussia Dortmund, Pulisic struggled for playing time during Tuchel's time at Stamford Bridge and was linked with a move away from Chelsea this summer. An exit never materialized and Tuchel was replaced as coach by Graham Potter earlier this month.

Adding further insight into his strained relationship with Tuchel, Pulisic said that his goal against Madrid came after ignoring advice from his then-manager.

"As I take off on the run, I hear Thomas Tuchel yelling from the sideline, 'Christian, stay in the pocket, don't make the run!' he wrote. "But I just had the feeling I'd find the space and get on the end of the pass, so I continued the run."

Pulisic did come off the bench in the second leg against Madrid and assisted Chelsea's second goal of a 2-0 win. The Hershey, Pennsylvania, native said when he did get on the pitch "he was so wound up" and that his assist for Mason Mount was "probably my favorite I've ever made."

Despite the change in coach, Pulisic was only a late substitute in Potter's first game in charge, a 1-1 draw with FC Salzburg in the Champions League last week.

Pulisic, 24, is set to be a key player for the U.S. at this year's World Cup in Qatar, where they will face Wales, England and Iran in the group stage. The tournament begins on Nov. 20.