BUDAPEST (AFP) - Reserve driver Paul di Resta will replace unwell Felipe Massa in Saturday's qualifying and Sunday's race at the Hungarian Grand Prix, the Williams team confirmed on Saturday.

In a statement, the team said that Brazilian Massa had felt dizzy and unwell on Friday evening and had gone to hospital for tests.

He was cleared to take part in Saturday's practice session by the FIA medical delegate, but he felt unwell again during FP3 and has made the decision to withdraw from the weekend.

"Williams supports Felipe's decision and the team will work with him to ensure he makes a full recovery, with a view to return to the race track for the Belgian Grand Prix," said the team.

"Following this decision, the team's reserve driver Paul di Resta will drive alongside Lance Stroll for the remainder of the Hungarian Grand Prix weekend."

Briton Di Resta drove for the Force India team for three seasons from 2011 to 2013 and has taken part in a total of 58 grands prix, recording two fourth place finishes as his best results.