Professionalism arrived in Argentina in the early 1930s, though it wasn't fully established until 1934. In those early years of the decade, the championship was shared between Boca Juniors, River Plate and San Lorenzo — but it was the Xeneizes who became the first to win back-to-back titles, in 1934 and 1935. A domestic dominance that hadn't been seen since the mid-1910s, when Racing de Avellaneda built a four-season hegemony.
Boca possessed a fabulous attacking trio that delighted their supporters for several seasons: Pancho Varallo, Roberto Cherro and the Paraguayan Delfín Benítez Cáceres. The three were devastating across those two title campaigns, with Boca netting 199 goals in total — 101 in 1934 and 98 in 1935. Their supporting cast were equally impressive: on the right flank Luis Sánchez was the winger in the first title, replaced after his departure to Platense by Ricardo Zatelli, signed from River Plate — the first player, alongside Camilo Bonelli, to cross the divide in the professional era. On the left, Vicente Cusatti was the undisputed owner of that flank across both title seasons.
Sánchez and Zatelli were classic wingers — sharp pace, a good dribble and precise crosses into the box. Cherro and Benítez Cáceres played slightly deeper, almost as inside forwards. Cherro was a physically imposing player, nearly 80 kilos, but with exceptional quality — talented, technically sound, with a fine football brain and a dangerous shot. A genuine star. The Paraguayan, nicknamed "Machetero" after the Chaco War in which Paraguayan soldiers fought with machetes, was a small but powerfully built player, with a cannon of a left foot, a superb dribble and great cunning in his reading of the game. Up front, Varallo had a perfect marriage with goal — a spectacular finisher whose genius wasn't aesthetic, but was forged in strength, efficiency, a winner's mentality and the ferocity of his shot. Finally, Cussati was an agile, wily, clever left winger, effective in wide play and with a commendable first touch.

The formidable trio of Benítez Cáceres, Varallo and Cherro
Boca Juniors, managed by Mario Fortunato, deployed a simple, direct and effective brand of football. The defence was strengthened from 1935 onwards, while in midfield Lazzatti was the compass and conductor who linked up with the attack, leaving opponents empty-handed with his enormous quality and goalscoring strength. In both title campaigns, Independiente and San Lorenzo were formidable rivals who pushed Boca to near-perfection. In 1934, the red side finished just one point behind; the following year the gap grew to three, but San Lorenzo pushed them all the way. Boca built their first title on the lethal effectiveness of their attack: Cherro reached 22 goals, Benítez 20 and Varallo 18 — together accounting for more than 50% of the squad's total goals. Huracán were the first to suffer, conceding an overwhelming 0–4 at home on the opening day. But the first great win came against River Plate at home. The previous season's Millonarios had knocked them off the title on the final day — and this time Boca took full revenge. River arrived in form but fell 4–1, one of the best days for winger Sánchez with two goals. The match was also the first ever heavy defeat in Superclásico history in the professional era.
In direct meetings with their two great rivals, Boca won nothing — three draws against Independiente, two defeats and a draw against San Lorenzo. They therefore had to make up ground against sides where those rivals were less dominant. Against Vélez, for example, they relied on Roberto Cherro, who hit a hat-trick. Away to Platense, led by Lazzatti, both Cusatti and Pancho Varallo netted once each. Against Ferro and Chacarita it was Benítez Cáceres who stepped up with two braces, and on the day they completed their title-winning lap of honour Varallo again took centre stage. It was the penultimate matchday when Platense visited the Brandsen y Del Crucero ground and Boca needed only a win. Nerves were beginning to bite when Cherro opened the scoring on 30 minutes. From that moment the match became a formality — within three minutes Boca had made it 4–0, with two goals from Varallo and one from Zatelli. The visitors scored a consolation goal before Pancho rounded off his performance with a superb hat-trick.

Brandsen y Del Crucero — the ground where Boca played until 1938
In 1935, Fortunato remained in charge as the great Brazilian defender Domingos da Guía arrived — a signing that would define an era. Sánchez left for Platense and Zatelli took over on the flank, providing enormous assist work for Varallo, Cherro and company.
They beat Vélez at home on the opening day and by the second matchday had already landed their first big punch of the campaign — finally beating great rivals San Lorenzo, thanks to a Varallo goal. Unstoppable in the early phase, they put four past Argentinos Juniors and narrowly beat River — with a Cherro goal — recording their fourth consecutive win against the eternal rival. They also beat Quilmes 5–1 with a Varallo hat-trick, Racing in Avellaneda 4–2 and Chacarita 3–0.
The good run was interrupted by a home defeat to Independiente, which also spurred them on to a run of outstanding hammerings — against Gimnasia de La Plata, Quilmes, Lanús and Atlanta, who received eight goals in Buenos Aires, four of them from Benítez Cáceres in one of the finest days of his career in the Boca shirt. They beat San Lorenzo again, and after drawing with Independiente prepared to defend their title against Tigre on 18th December 1935, at their home ground of Brandsen y Del Crucero, winning 3–0 against the club from Victoria. The golden trident all scored: Cherro, Varallo and 'Machetero' Benítez Cáceres. The match was also historic because it would be the last time all three of Boca's great emblems scored in the same game.

The Boca championship-winning squad of 1934. Indicated left to right, standing and seated: Varallo, Cherro, Sánchez, Benítez and Cusatti