Temporary Promotion Didn't Go So Well. What next?

BLUF: I was given a 3 month temporary promotion to team leader (of my team) while the usual team leader was on 'special duties'.  My usual team leader has since fed back that people (other TL's) thought 'I'd make more of it' than I did.  I need people to know I can do the role (I'm passionate that I can) and need another opportunity should one arise.  Any tips please?

(background).

I had changed technical roles (fairly drastically) in the same company about 2 weeks before being asked to be temporary TL.  I'd worked in this kind of field before but not the depth I do now.

The old TL basically didn't disengage from his old role for the whole 3 months, didn't announce to the team I was the interim TL (actually seemed to refuse to accept it had happened!), didn't move office, attended the team meetings and acted as TL, kept on undermining me in meetings (reporting on his 'old' team that I was TL of when he was there to report on his current team).  A lot of the time it got pretty tense (his boss picked him up on this).

At a recent meeting with him, when I said I didn't feel I had achieved as much as I wanted during the 3 month period, he said that other people had said that about me too.

This really bugs me, because I don't think I was given a fair shot at it.  I knew he was coming back after 3 months, so didn't want to make sweeping changes, ok we didn't deliver to target (but for the last 2 years neither did the team anyway!) but I reckon I put in a good groundwork of planning and communication and leadership that has benefitted the team since.  He acknowledges this (which is good I guess).

I just feel that if people don't reckon I did 'well' during the 3 months, they might overlook me if another such opportunity (or full time TL role) came up and I really have to make sure I'm the 'best' in everyone's eyes to take on such a role.

Any ideas please?  I am currently thinking about the option of talking to his boss directly about this.

thanks,

Fitch.