Unchallenged

Adjective

 * 1) Not having any challengers.
 * 2) Lacking experience due to lack of challenges; untested.

Thesaurus
agreeing, at one, at one with, beyond question, carried by acclamation, concordant, concurrent, consentaneous, doubtless, in agreement, indubious, like-minded, of a piece, of one accord, of one mind, past dispute, questionless, solid, unanimous, uncontested, uncontradicted, uncontroversial, uncontroverted, undisputed, undoubted, unopposed, unquestioned, with one consent, with one voice

Related terms

 * challenge
 * challenged
 * unchallengeable