Antonio Conte has recalled Gary Cahill with the skipper replacing Andreas Christensen in the middle of defence while Thibaut Courtois is fit to return in goal.
Former Manchester United striker Hernandez, on as a substitute, levelled things up 17 minutes from time, cancelling out Cesar Azpilicueta's first half opener.
Moyes' side weathered the early storm, however, and could have taken the lead themselves in the 14th minute when Marko Arnautovic pulled down a long ball in the penalty area.
"I've always thought that if you win 10 games in a Premier League season, then you will be safe because you'll also pick up points with draws".
When all is said and done at the end of Javier Hernandez's career it will be criminal if he isn't included in the same discussion as Ole Gunnar Solskjær as the Premier League's greatest-ever super sub.
Having found the first goal, the Blues maintained the momentum in a bid to double their lead before the referee would signal the end of the first half, but that didn't come as the first stanza of the encounter ended 1-0 in favour of the Blues.
"Chich" has come back from the other side of the world last week.
With six games left, Chelsea can still mathematically reach the Champions League, although that would require a collapse from both Liverpool (who have five games remaining) and Tottenham (who have six games to play). "They created a lot but we stood strong". They create chances, they are ready to suffer and win the game.
The Hammers have become something of a bogey side for Chelsea in recent years but this match could serve to re-address the balance back in favour of the Blues.
Tottenham won their first game at the west London club since 1990 last weekend after goals from Christian Eriksen and Dele Alli sealed a 3-1 win over Chelsea FC at Stamford Bridge last weekend.