The paper describes the PSI team developed at Program Systems Institute of Russian Academy of Science. We propose a dynamical refinement method of plans with defaults for the construction of software agents playing soccer. The architecture of our agents is composed of two main parts: the set of elementary plans and the planning system. The planning system uses on-line plan refinement procedure for constructing plans with elementary ones. There are some default conditions of normal continuation associated implicitly with each plan. The purpose of the refining process is to add new actions to the initial plan in order to maintain or recover normal continuation of the plan.