Samuels was named as replacement for the injured Quinton de Kock for the remainder of the Indian Premier League (IPL) season.
De Kock, the South African wicketkeeper-batsman, was ruled out due to injury ahead of the season.
"He is going to join us on the 29th. He will definitely boost the side," Zaheer said.
A veteran of 71 Tests, 187 One-Day Internationals and 55 Twenty20 Internationals, Samuels has played for one IPL franchise in previous editions.
Delhi are seventh in the points table having won only two games in six outings so far.
Source - Agency
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