Real Madrid coach Santiago Solari will have to decide between youth and experience as his side looks to take another step towards a historic fourth consecutive Champions League title on Wednesday.
Real travel to play Ajax in Holland in their best form of the season after last week drawing away to FC Barcelona in the Camp Nou Stadium in the Copa del Rey and following that up with a 3-1 win over Atletico Madrid to lift them to second in the Liga Santander, six points behind FC Barcelona.
Those two games highlighted the question Solari has to resolve in Holland: against Barcelona he played the experienced Marcelo at left back and watched as Barca picked on the Brazilian time and again, exposing his poor positioning and clearly marking him as the weak link in the Madrid defense.
The coach dropped Marcelo for the trip across town on Saturday with former B-teamer Sergio Reguilon given the nod at left back, where he responded with another assured defensive performance.
Reguilon has made only nine league and two European appearances, compared with Marcelo's 12 years at the club, but at the moment he appears to be the more secure defender.
Perhaps nobody typifies Madrid's turnaround under Solari more than Vinicius Jr, who has brought freshness to the attack, with the Brazilian's willingness to run at rivals a key factor in Karim Benzema's current goal-scoring form.
The Brazilian is likely to start in Amsterdam with Gareth Bale on the subs' bench, which shows that as in the case of Marcelo and also Isco, Solari is not afraid to leave experienced players out of the side.
There is also a view that Bale can be very effective using his pace against tired rivals in the last 20 minutes of games as he did on Saturday.
Solari will be without another of the youngsters who have impressed since his arrival. Marcos Llorente is sidelined with a thigh injury that will keep him out until March, but with Lucas Vaquez in form and Luka Modric returning to somewhere close to his best, the rest of the team will virtually pick itself with Thibaut Courtois in goal, Dani Carvajal Sergio Ramos in defense, Modric, Korros and Casemiro in the middle and Benzema and Vazquez up front.