**The Ospreys' bid to top the Welsh Shield takes centre stage in the United Rugby Championship this weekend, while the European destiny of four other URC sides will be on the line in the Heineken Champions Cup and EPCR Challenge Cup quarter-finals.** There have also been some significant transfers and contract renewals this week, while retirement has come even earlier than planned for one of the competition's stars. Here are five things to know ahead of the weekend.
