With 15 minutes to play, Thomas Tuchel decided to go all-in against West Ham United. The Chelsea head coach had already instructed Hakim Ziyech to ready himself but decided the Moroccan alone wouldn't be enough to win what had been an attritional contest at Stamford Bridge. Further firepower was needed.
So Christian Pulisic and Romelu Lukaku were called back from their respective warm-ups and joined Ziyech in the dugout. Moments later, the trio were introduced in unison by Tuchel. It felt like a statement of intent, a warning to West Ham that there would be no let-up in the closing stages as Chelsea searched for a winner. And so that proved.
Ziyech and Pulisic combined instantly down the Blues' right. Lukaku lurked with menace on the shoulder of Craig Dawson, who had been imperious in the West Ham defence during the contest but hadn't been overly troubled by either Timo Werner or Kai Havertz, the latter of which had spent much of the game on the right flank.
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Lukaku hasn't had it easy over the past two months. He has started just one Premier League game – against Arsenal –and that ended with him being replaced on the hour mark and booed by a minority of his own supporters. Yet he had an impact against West Ham, just as Tuchel wanted and almost certainly demanded when the Belgian stood on the touchline prior to his introduction.
It was Lukaku who won Chelsea's penalty; the striker pulled down, having forced his way past Dawson in chase of a Thiago Silva flick-on. That Jorginho wasted the opportunity from 12 yards was a painful moment, one that had the potential to leave the Blues disappointed. Fortunately, another substitute stepped up.
As the game ticked into its 90th minute, Mason Mount knocked the ball onto Marcos Alonso down the Chelsea left, and the Spaniard delivered a loss cross into the penalty area. Pulisic was on hand to meet it and swept his left-footed finish into the bottom corner to secure the hardest of fought wins for Tuchel's side.
"It was nice for Hakim, for Romelu and Puli especially to be so heavily involved from the bench, it was exactly what we needed," a pleased Tuchel told Chelsea's in-house media after the game. "To win was very important because Arsenal won again, and they beat us [in midweek]."
West Ham club captain, Mark Noble, was a little more effusive in his assessment of the trio – which the Blues invested £188million to sign – that helped the Blues come out on top. "For Chelsea to be able to bring on Romelu Lukaku, Hakim Ziyech, and Christian Pulisic, who scored the goal… it's phenomenal," he admitted in an interview with West Ham TV.
Tuchel hasn't always got his changes right during his Chelsea tenure. Nor have they always been prompt, something that has become a minor grumble among supporters. In the Premier League this term, only five of the Blues' goals have been scored by substitutes, a figure some way behind Manchester United (10) and Liverpool (9).
As highlighted against West Ham, Chelsea does not lack quality from the bench. The problem is that quality hasn't always been married with form this term. There have been occasions that Tuchel has thrown on an attacking player in hope rather than expectation – and that must change next term if the Blues are to have any hope of mounting a title challenge.
In Pulisic, however, Chelsea do possess a player adept at making an impact in limited minutes. His strike against West Ham was his second as a substitute this term, and Tuchel has spoken previously about the role the American can play off the bench. "He (Tuchel) just said to make a difference," Pulisic told Sky Sports after his goal against West Ham. "I needed to come in and make a difference and show I want to be playing."
Pulisic has struggled to break back into the starting XI after the international break earlier this month. Tuchel stated that is by design, however, during his post-match press conference. "Puli struggled a little bit since coming back from the international break where he had three matches, an incredible amount of joineries and timezones to cope with. From there, he struggled energy-wise.
"This was my impression, on and off the pitch. It's sometimes like this. Now we have tried to bring him back in full confidence from the bench, and I am happy with the effort today and I am happy he had the chance to have this big impact with Romelu and Hakim. It was super important."
Pulisic's winner means Chelsea needs just seven points from their remaining six Premier League matches to secure Champions League football for next season. The next opportunity to chip away at that total will come on Thursday night against Manchester United.
Again, Tuchel will have to disappoint several of his attackers at Old Trafford, but he will hope that, if needed, those called upon from the bench can make the same impact that Ziyech, Pulisic and Lukaku managed against West Ham.
