That is the suggestion of former midfielder Jan Molby.
Liverpool travel to Vicarage Road looking to maintain an unbeaten start to the Premier League season which has largely hinged upon their reliable defence.
They have conceded just five goals in 12 games so far – a joint-league best alongside leaders and title rivals Manchester City.
Van Dijk and Gomez have been Jurgen Klopp’s main partnership and have been praised as two of Liverpool’s best performers this season.
But on occasion, Klopp has altered his line-up and switched Gomez to right-back while Joel Matip came in to replace the England youngster against Southampton.
And though Van Dijk and Gomez are widely viewed as the Merseyside outfit’s best pairing at the back, Molby believes the situation is not as easy as picking the duo whenever they are fit and available.
He told the Liverpool Echo: “Liverpool’s centre-back positions have become a talking point among Reds fans, with many regarding Gomez as Van Dijk’s first-choice partner. I don’t think it’s as clear-cut as that.
“Klopp will be aware of what each centre-back can do, and a lot will revolve around the manager’s thoughts about Trent Alexander-Arnold’s form.
“Trent played at Watford last year and had a few problems, and if a little more defensive solidity is needed it wouldn’t surprise me if Gomez moved to right-back and Dejan Lovren came in at centre-back.”
And Molby has warned Liverpool simply cannot slip up at Watford tomorrow (3pm) – where they drew 3-3 on the opening day of last season.
While the Hornets have faded away slightly since starting the current campaign with five straight wins, they did beat Tottenham at home earlier in the season.
The Dane added: “If Liverpool are serious about being the team to keep pace with Manchester City, they have to find a way to beat Watford.
“This will be a big game in Watford’s calendar and the stadium will be buzzing. This is like going to Bournemouth and Everton, they are all very difficult away games.
“Watford won’t be easy. They started the season strongly and the reason they have tailed off in recent weeks is because they are, at best, a top 10 team.
“But they have some real quality and have various ways they can hurt you.
“Watford are a big strong team and very mobile, and if you catch them on a day when they’re at it, they can be a handful.
“It’s going to be a really, really tricky game. I’ve seen Watford a few times this season and I like them, and as everyone knows I’m a big fan of Abdoulaye Doucoure in midfield.”