Chad's supreme court has cleared President Idris Deby, who has been in power for 30 years, to seek a sixth term in office in the 11 April presidential election.
He faces nine other candidates who were qualified by the supreme court, including his main and historical rival, Saleh Kebzabo.
The inclusion of Mr Kebzabo, who had on Monday withdrawn his candidacy, has raised questions.
The opposition leader had cited the "obvious militarisation of the political climate" following the deadly attempt by security forces to arrest another opposition candidate, Yaya Dillo, at his home in the capital, N'Djamena.
The 28 February attack left five members of Mr Dillo’s family dead, according to his party, although the government says three people were killed, including the mother of the opposition leader.
The supreme court rejected the candidacy of seven other aspirants including Mr Dillo and Succès Masra on grounds that their parties were not "legally constituted".
With the crackdown on a fractured opposition, the incumbent is now seen as the favourite to win re-election for a 6th term.