The two clubs remain level on 10 points with Deportivo Saprissa at the helm of the standings, after their stalemate at the Estadio Jose Rafael Fello Meza in Cartago.
The draw ended both sides' winning runs, although Cartagines remain unbeaten in 13 in all competitions, and UCR's streak without loss reached five matches.
Limon opened their account in the Torneo de Invierno phase, with a 3-1 home win over Santos de Guapiles.
Winston Parks and Alexander Espinoza both scored in the 10 minutes prior to half-time, although Santos gave Limon some nervous moments when they pulled one back through Antonio Salazar with 17 minutes to play.
But Limon responded well, regaining a two-goal buffer when Steven Calderon scored five minutes later.
Perez Zeledon's up-and-down season continued, as they earned a 2-1 win away at Carmelita.
The club has gone loss-win-loss-win so far, but they were on the right side of the ledger on Wednesday courtesy of goals to Fabrizio Ronchetti and Roy Myrie.
Promoted Puma Generalena won their first match in the top flight, downing Uruguay 2-1.
Ronald Salas and Alban Gomez had the hosts 2-0 up after 35 minutes, and Uruguay's Joshua Diaz pulled one back in the second half - but it would be rendered consolation.
Scheduled mid-week fixtures pitting Alajuelense against Herediano, and Deportivo Saprissa against Belen Siglo XXI, were postponed due to the ongoing Copa Centroamericana.
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