The pair have been named on the wings for Glasgow's Hughenden match against Connacht.
Rory returns to the team after more than a month's injury absence. He damaged a hamstring in the league match against Cardiff at The Arms Park on 13 November. He also played in the previous Glasgow match, the 36-22 win against The Borders at Hughenden, but Sean was on Scotland duty those weekends.
This morning, after the final training run before tomorrow's match, Rory recalled the last time he played alongside his brother. "I was probably 17, he was 18 or 19," Rory explained. "It was for Melton Mowbray Colts. He was at scrum half, I was fly half." They are now 23 and 22.
Glasgow have made three changes in personnel from the team who started in the 22-38 defeat by Llanelli Scarlets in the Heineken Cup match at Stradey Park on Sunday.
Two of the changes are in the back division. Rory Lamont replaces Gareth Maclure, and Glasgow Hawks' Colin Shaw returns at full back for Kenny Logan, the Scotland cap who had to have hospital treatment after a head-on collision with David Hodges in the Stradey Park cup match.
It will be Shaw's third start for Glasgow. The former Scotland under-21 cap played in the league matches against Llanelli and Leinster last month, scoring a try in the latter game.
In the only change in the pack Scott Lawson starts as hooker in place of Gordon Bulloch, Scotland's captain in last month's Tests.
Dan Parks, Scotland's stand-off in the autumn Tests, returns to the Glasgow squad, though as a replacement. After his November duties with Scotland he flew out to Australia for his brother's wedding last weekend.
Glasgow have won their past three home league matches, successively against Ulster, The Borders, and Llanelli. It is a sequence they are determined to extend, not least to move away from Connacht in the league table. Glasgow are fifth, heading the western Irish province only narrowly on points difference.
"It's a crunch game," Hugh Campbell, Glasgow's head coach, remarked today. "We're level on points. If we win, we would go up - if they win, they'll move up."
15 Colin Shaw; 14 Rory Lamont, 13 Graeme Morrison; 12 Andy Henderson, 11 Sean Lamont; 10 Calvin Howarth, 9 Graeme Beveridge; 1 Kevin Tkachuk, 2 Scott Lawson, 3 Euan Murray; 4 Andy Hall, 5 Dan Turner; 6 Andrew Wilson, 7 Donnie Macfadyen,8 Jon Petrie (captain)
Replacements: 16 Gordon Bulloch, 17 Andrew Kelly, 18 Joe Beardshaw, 19 John Beattie, 20 Sam Pinder, 21 Dan Parks, 22 Gareth Maclure
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