Welbeck represents a change in transfer strategy from Chelsea's owners, who have predominantly looked to sign younger players since their takeover in 2022.
His arrival also raises question marks about the future of Chelsea's other centre-forward options.
Joao Pedro is regarded as the club's first-choice option, while they also have Liam Delap, Emmanuel Emegha, Marc Guiu and Nicolas Jackson on their books.
He spent five years in north London before joining Watford, moving to Brighton in 2020 after a single season with the Hornets.
Welbeck has scored 16 times in 42 appearances for England. His last cap came in 2018 and he was overlooked for a place in Thomas Tuchel's 2026 World Cup squad.
Why Alonso sees value in Welbeck
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Figure caption,
Chelsea sign Welbeck - watch all of his Premier League goals from last season
ByPrudent NsengiyumvaSport journalist
At 35, some Chelsea supporters might raise eyebrows. The club has spent the past three years building one of Europe's youngest squads, and Welbeck sits well outside that profile. But look closely and you start to understand why Xabi Alonso is interested. He offers qualities the Blues' current forwards don't consistently provide.
Welbeck's appeal is rooted in reliability and movement. His 13 league goals for Brighton last season came from 12.5 expected goals, a steady return that reflects a striker who finishes at expectation and rarely wastes chances. His big chance conversion rate (47.6%) sits narrowly behind Joao Pedro (53.9%) and ahead of Nicolas Jackson (41.2%), who spent last season on loan at Bayern Munich.
What separates him is how he knits attacks together. Welbeck's 132 runs in behind show he still stretches defences, but he also contributes clean, simple link play. He created 20 open play chances for the Seagulls last season, and remains efficient with his shooting, hitting the target with almost half of his attempts.
Out of possession, he shows age is just a number. He still works with Premier League intensity. Welbeck averaged 32 pressures per 90 in the final third, comparable to Pedro and ahead of Jackson, showing he can slot into Alonso's pressing structure without adaptation. You can't sniff at his durability either - 37 league appearances, 26 of them starts.
Welbeck wouldn't necessarily redefine Chelsea's attack. But he would give the Alonso another dimension. A selfless, tactically disciplined forward who links phases and presses intelligently.
Welbeck can finally stop scoring against Chelsea...
