Optical Burst Switching (OBS) has been envisioned as a cost-effective paradigm for supporting IP packet traffic over optical transport networks. OBS network performance is hampered by resource contention at the network core nodes, requiring efficient strategies for avoiding and/or resolving contention. Strategies acting in the space domain can be exploited to achieve this goal without imposing additional hardware requirements on the core nodes. Previous works have focused either on reactive routing strategies, namely deflection routing, or on proactive routing strategies. This paper assesses the outcome of combining proactive routing for minimizing contention in advance with deflection routing for resolving contention. Using network simulation it is shown that the combined approach significantly improves the network performance over the use of only one routing strategy.