Physiological effects

Massage is thought to induce a variety of positive physiological effects (Wright and Sluka, 2001), that may contribute to tissue repair, pain modulation, relaxation, and improved mood and that has beneficial effects on arterial and venous blood flow and edema (Goats, 2004).
Massage at the physiological level:

Increasing local Temperature.
Increasing Blood Flow.
Promoting parasympathetic activity.
Promoting the liberation of neuroendocrine substances.

Summarizing the effects of the massage we can conclude that it has different actions on the body. These actions are the basis for its therapeutical effects:

Anti-inflammatory activity
Analgesic activity: Pain reduction
On Musculoskeletal System: Massage by direct pressure and by increasing circulation helps to relieve muscular restrictions, muscle tension and stiffness, tightness, and spasms,, resulting in more flexible, supple, and resilient muscle tissues.
On connective tissue
On Bones
On Skin
On Cardiovascular system
On vessels and lymphatic systems
On activities on recovering, increased healing rate and tissue repair
On immune response: The stretching produced by the massage on the skeletal muscles (Hornberger, et al, 2005; Kumar et al, 2002), activates the kinase cascades and the regulatory factors that modulate protein synthesis, glucose uptake, and immune cell recruitment (Cara et al, 2001; Chambers et al, 2009; Hornberger et al, 2006).
Psychological and mental benefits