The Mexican youngster scored three goals in the second half to inspire America to a late come-from-behind victory in the opening leg of their quarter-final tie at the Estadio Azteca on Wednesday.
With scores level at three-apiece inside the final three minutes of normal time, Jimenez netted his third of the game before Rubens Sambueza struck in the 93rd minute to cap a superb fightback from the home side.
Despite prevailing in an eight-goal thriller, the tie remains in the balance ahead of Saturday's return leg after Santos Laguna scored three priceless away goals.
Antonio Mohamed's America stormed out of the blocks on Wednesday with Osvaldo Martinez opening the scoring on 14 minutes courtesy of a rebound from close range.
But it was one-way traffic from that point after goals from Rodolfo Salinas, Carlos Quintero and Ribair Rodriguez put the visiting side 3-1 ahead nine minutes into the second half.
Jimenez sparked America's revival with a goal on the hour mark before putting the hosts ahead thanks to two strikes in the space of six minutes late on.
Sambueza got in on the action in the third minute of injury time, though the win was soured by Francisco Rodriguez's red card during the closing stages.
Elsewhere on Wednesday, Cruz Azul earned a 1-1 draw from their trip to Leon.
The recently crowned CONCACAF Champions, who topped the standings in the regular season, hit the front in the fourth minute thanks to striker Mariano Pavone.
Jose Cardenas restored parity on 21 minutes at the Estadio Leon, leaving the clash evenly poised.
On Thursday, Pumas UNAM salvaged a 1-1 draw against Pachuca at the Estadio Miguel Hidalgo.
Dario Carreno's 71st-minute opener had the home team seemingly on track for a narrow win but Javier Cortes's equaliser in the dying moments ensured honours were even.
Meanwhile, Tijuana and Toluca played out a goalless draw at the Estadio Caliente.
