AS are running some sort of PR-campain against marcelo & drenthe or, depending on ones point of view, in favor of marcos alonso.
marcos alonso, 18, is the castillas LB and has trained about 5 times with the first squad, including during pre-season. AS claim pellegrini has been watching marcos alonso for a long time and monitored him as an alternative to marcelo (alledgedly, he has no faith at all in drenthe) and regards him as the future LB.
personally i haven't seen him play, but i'm always in favor of giving cantera boys a chance to prove themself. IMO he can't be much worse than marcelo or drenthe. therefore i would give him a chance and see how he does, especially since i'm no fan of RBs swichting on the left side (arbeloa, m. torres)...it's just not a serious alternative for a natural LB with a strong left foot. the only RB that was doing a great job as LB is IMO phillipp lahm.