Messi scored twice as the La Liga giants won the second leg 3-0 to set up a quarter-final tie with Roma.
But despite Barca’s comfortable win, reports in Spain suggest that Messi was impressed with Alonso’s performances over the two games.
The report suggests that Messi is likely to take over as captain when Andres Iniesta leaves and is therefore more interested in Barca’s transfer dealings.
The 30-year-old is desperate for new faces and wants competition for Jordi Alba at left-back.
Barcelona are currently 11 points clear at the top of La Liga after beating Athletic Bilbao this afternoon.