Marcos Alonso makes his first appearance since the win at Spurs before Christmas in a side showing eight changes.
Fikayo Tomori and Kurt Zouma join him in defence with captain Cesar Azpilicueta at right-back, ahead of Willy Caballero in goal.
Mason Mount returns to the starting line-up in midfield with the forward line the same one that began against Nottingham Forest in the last round of the FA Cup., with Michy Batshuayi as the spearhead.
Hull make four changes with Tom Eaves, Robbie McKenzie, George Honeyman and Mallik Wilks coming in.
Chelsea: Caballero; Azpilicueta (c), Zouma, Tomori, Alonso; Barkley, Kovacic, Mount; Hudson-Odoi, Batshuayi, Pedro.
Subs: Cumming, Lamptey, Christensen, Emerson, Maatsen, Gilmour, Willian.
Hull: Long; Lichaj (c), Burke, Tafazolli, McKenzie, Kane, Da Silva Lopes, Wilks, Bowen, Honeyman, Eaves.
Subs: Ingram, Grosicki, MacEnnis, Mclaughlin, Kingsley, Irvine, Samuelsen.
The referee is Craig Pawson.
Chelsea are seeking to reach the FA Cup fifth round for the 23rd time in 26 attempts.The fourth-round FA Cup draw has matched Chelsea with Hull for the eighth time, and second in three seasons. The Blues have never lost to the Tigers in this competition, though three of the first four ties between 1909 and 1982 were only won after a replay.Chelsea have won the last seven meetings in league and cup and are unbeaten in 15 games against the Tigers (13 wins, two draws).
Chelsea have been drawn away in the FA Cup for the first time since the quarter-final at Leicester in 2018.The last team from a lower division to beat the Blues in the FA Cup was Bradford City in the fourth round in 2015 at Stamford Bridge. The Bantams were sixth in League One at the time and ended our run of 12 successive home victories by winning 4-2.Frank Lampard’s side have won 60 per cent (nine) of our 15 away games this season in all competitions, losing four.In his playing career for the Blues, Frank Lampard played five times against the Tigers, winning three and drawing the other two, scoring twice.
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