The 20-year-old has yet to feature for the Blues since joining the club, but has made encouraging progress in training and could be included in the squad for Sunday's Premier League trip to the Stadium of Light.
Anselmino has also received his first call-up to the Argentina national team, joining Emiliano Martínez and Valentín Barco in the squad. Alonso believes the recognition is an important moment for the young defender, who has been working towards full fitness.
“He’s doing everything, and tomorrow [Saturday] we’ll decide, but he could be in the squad, yes,” the Chelsea manager said.
“They [Argentina] asked us and he has been training better for the last ten days, and it’s very important for him to have this first call-up.”
The potential return of Anselmino is one positive in an otherwise uncertain fitness picture for Chelsea ahead of their visit to Sunderland.
Alonso is also waiting on the availability of Moisés Caicedo, who missed training earlier in the week after experiencing discomfort following the victory over Manchester United.
The Ecuadorian has been out on the grass at points during the week, but the manager will not make a final decision until after Saturday's last training session.
“He’s doing bits and other bits,” Alonso explained, indicating that Caicedo's condition will be assessed before the squad travels north.
The midfielder's issue was described as discomfort rather than a recurrence of his previous calf problem, but Chelsea are taking care over his availability.
Anselmino's possible involvement would offer another option in defence, while his Argentina selection provides a further indication of the progress he has made during his recovery.
For the youngster, the immediate priority is earning his first Chelsea appearance. Sunday's fixture could provide that opportunity, although Alonso will wait until the final session before confirming his plans.