Welbeck has scored 46 goals in 176 Premier League appearances for Brighton, having previously played for Manchester United and Arsenal among other clubs.
Chelsea currently have five recognised strikers on their books in João Pedro, considered untouchable, along with Emmanuel Emegha, Liam Delap, Nicolas Jackson and Marc Guiu, and have been looking at sales or loans to trim their options up front even as they explore a move for Welbeck, according to the Daily Mail.
The forward scored 13 times in the Premier League for Brighton last season, a career-best return that also saw him considered unfortunate not to make England's squad under Thomas Tuchel. Welbeck joined Brighton from Watford in 2020 and triggered a one-year contract extension in March, meaning his current deal runs until the end of the 2026-27 season.
Should he move to Stamford Bridge, he would add to a lengthy list of players Chelsea have signed from Brighton in recent years, including Marc Cucurella, Moisés Caicedo, Robert Sánchez and João Pedro himself.
João Pedro, Emegha and Delap are currently with the squad on Chelsea's pre-season tour of Australia and Asia, while talks over Welbeck continue in the background.
According to The Athletic, Alonso has identified the veteran as a priority target as he looks to balance a young Chelsea squad with proven Premier League experience, valuing both his goal return and his standing as a leader within a dressing room. Brighton are said to be aware of the interest but have not yet indicated whether they would be willing to sanction a sale of one of their most productive players from last season.
The move would mark a significant departure from Chelsea's recruitment strategy in recent windows, which has focused heavily on signing young players with long-term potential rather than the kind of experienced, proven performer Welbeck represents.
Alongside Welbeck, Chelsea have also been credited with interest in other established Premier League figures this summer, including Sunderland captain Granit Xhaka and free agent John Stones, as Alonso looks to add maturity and leadership to a squad still finding its feet under its third permanent manager in less than a year.