Ralf Schumacher has suggested that Red Bull boss Christian Horner remains unconvinced by Yuki Tsunoda, despite promoting the Japanese star to the team this week.
Lawson got the nod over his former team-mate to take the spot vacated by Sergio Perez during the off-season, but endured a dismal start to the year having failed to score points in either of his first two outings.
"Red Bull, it has to be acknowledged, would already have sunk into mediocrity if they didn't have Max Verstappen, who somehow pulls the chestnuts out of the fire," Schumacher told Sky Sports Germany.
"Then there's Dr. Marko; there's no agreement internally with the drivers. Because one thing was clear: Dr. Marko naturally wanted to take two drivers from his own squad for Red Bull.
"That meant Lawson or Tsunoda. Neither of them is very highly regarded by Horner."
Red Bull currently sit 42 points behind leaders McLaren in the constructors' championship, with their chances of regaining their title from the British outfit hanging by a thread.
There are also concerns over whether Verstappen can hold on to his drivers' crown, with the Dutchman already looking like he's struggling to keep up with the pace of Lando Norris and Oscar Piastri.
The team will look to get their faltering season back on track at next weekend's Japanese Grand Prix, where Tsunoda will make his Red Bull debut in front of his home fans.
Lawson, on the other hand, will look to shrug off his disappointment by putting in a strong performance alongside new Racing Bulls team-mate Isack Hadjar at the Suzuka Circuit.