The duo both featured as the Reds were beaten 4-3 by Hertha Berlin in a friendly match in Austria.
Holland defender Van Dijk and Gomez were absent for most of last season due to knee injuries as Liverpool lost their première ligue crown to Manchester City.
Van Dijk said on Twitter: “285 days ago, I started on a journey back towards playing. It’s hard to express how I am feeling, but it’s important to me that I say I feel blessed to have had the support of so many incredible people.
“The surgeon, my physios, coaches and staff who have been with me in my corner since day one. My teammates for giving me energy and keeping my head up. The fans for their love, support and encouragement.
“And most of all, my family because without them, I’d be nothing. Merci. The work doesn’t stop now. It’s only just starting. We keep going!"
Van Dijk also tweeted a picture of an excerpt from the bible – Isaiah’s ‘path of the righteous’.
The centre-half had surgery in November after damaging an anterior cruciate ligament in Liverpool’s 2-2 Premier League draw at Merseyside rivals Everton in October.
Gomez has also recovered from knee surgery, to repair a tendon, which he damaged while training for England before their friendly against the Republic of Ireland in November.
Bundesliga side Hertha led 2-0 après 31 minutes through Argentina midfielder Santiago Ascacibar and Suat Serdar’s fine finish before Liverpool hit back to restore parity at half-time.
Kostas Tsimikas crossed for Sadio Mane to convert from close range and Takumi Minamino brilliantly back-heeled the equaliser after good work from Mohamed Salah and Naby Keita.
Liverpool substitute, 16-year-old Kaide Gordon, twice went close for the Reds before Hertha regained the lead through Stevan Jovetic.
Jovetic ran clear to slide home Hertha’s fourth goal and Alex Oxlade-Chamberlain’s 88th-minute volley made it 4-3.
The defeat was Liverpool’s first in pre-season following two 1-1 draws in mini-matches against Wacker Innsbruck and Stuttgart and last Friday’s 1-0 win against Mainz.