Watford - Bournemouth edged further away from the Premier League relegation zone following a 0-0 draw at Watford on Saturday.
Watford top scorer was unable to convert a hatful of chances at Vicarage Road, while Heurelho Gomes made a string of fine saves late on to deny Bournemouth.
The Cherries moved five points clear of the bottom three after halting a run of successive defeats and have lost just one of their last eight on their travels, while Watford dropped one place to 10th.
Watford boss Quique Sanchez Flores and Bournemouth counterpart Eddie Howe both made wholesale changes to their respective sides after suffering differing fates in the FA Cup fifth round last weekend.
Ighalo, recalled to the Watford team after he was rested for last Saturday's 1-0 win over Leeds United, was denied early on by a sharp save from Bournemouth goalkeeper Artur Boruc.
The Nigerian then volleyed wide from Juan Carlos Paredes' right-wing cross shortly after, with Bournemouth winger Max Gradel, back from a serious knee injury, coming on for his first appearance since August when he replaced Junior Stanislas midway through the first half.
Ighalo wasted a glorious chance on 67 minutes when he headed over from close range after fine work from Nordin Amrabat, but the Hornets were also indebted to a series of stops from Gomes as Bournemouth upped the pressure.
First the Brazilian kept out a stinging long-range shot from Harry Arter, with Gomes then saving from Dan Gosling and denying Gradel twice to keep Bournemouth at bay.